Effect of adipose-derived mesenchymal stromal cells on tendon healing in aging and estrogen deficiency: an in vitro co-culture model.

BACKGROUND AIMS: Aging and estrogen deficiency play a pivotal role in reducing tenocyte proliferation, collagen turnover and extracellular matrix remodeling. Mesenchymal stromal cells are being studied as an alternative for tendon regeneration, but little is known about the molecular events of adipose-derived mesenchymal stromal cells (ADSCs) on tenocytes in tendons compromised by aging and estrogen deficiency. The present in vitro study aims to compare the potential therapeutic effects of ADSCs, harvested from healthy young (sham) and aged estrogen-deficient (OVX) subjects, for tendon healing. METHODS: An indirect co-culture system was set up with ADSCs, isolated from OVX or sham rats, and tenocytes from OVX rats. Cell proliferation, healing rate and gene expression were evaluated in both a standard culture condition and a microwound-healing model. RESULTS: It was observed that tenocyte proliferation, healing rate and collagen expression improved after the addition of sham ADSCs in both culture situations. OVX ADSCs also increased tenocyte proliferation and healing rate but less compared with sham ADSCs. Decorin and Tenascin C expression increased in the presence of OVX ADSCs. CONCLUSIONS: Findings suggest that ADSCs might be a promising treatment for tendon regeneration in advanced age and estrogen deficiency. However, some differences between allogenic and autologous cells were found and should be investigated in further in vivo studies. It appears that allogenic ADSCs improve tenocyte proliferation, collagen expression and the healing rate more than autologous cells. Autologous cells increase collagen expression only in the absence of an injury and increase Decorin and Tenascin C more than allogenic cells.

Hydrogen Peroxide: Its Use in an Extensive Acute Wound to Promote Wound Granulation and Infection Control - Is it Better Than Normal Saline?

Background: Hydrogen peroxide (H2O2) is used as a topical antiseptic in contaminated wounds caused by road traffic accidents. It kills bacteria by producing oxidation through local, nascent, free oxygen radicals. It also removes dirt from the wound due to its frothing action. H2O2 is synthesized by various cells as an active biochemical agent that affects cell biological behavior through complex chemical reactions. H2O2 has also been used as a wound cleaning agent, removing debris, preventing infection, and causing hemostasis due to its exothermic reaction with blood. Despite its widespread use, there is scanty literature on its use to promote granulation tissue formation. Objective: In the orthopaedics literature, studies on H2O2 use are very limited and its potential is underestimated. In the present study, we would like to report our protocol of use of H2O2 for its tremendous potential for stimulating granulation and early wound healing. Material and Methods: A total of 53 patients with large acute extensive lower limb contaminated wounds reported to the emergency department have been included with and without lower limb fracture. In group A (43 patients) wound management was done using 7% H2O2 and group B (10 patients) was treated by only saline dressing as a control group. Results: In the present study, daily dressing by 7% H2O2 solution and provide solution gives excellent results compared to the Saline group. Granulation tissue appeared much earlier with a mean SD 6.3 ± 6.8 days in the hydrogen peroxide group as compared to the Saline group where granulation tissue appeared in 9.3 ± 8.4 days. Conclusion: Spontaneous wound healing is a controlled balance between destructive and healing processes. It is mandatory to remove damaged tissue to promote healing by secondary intention and minimize infection. The dynamic effect of H2O2 promotes faster healing, stimulates granulation, and minimizes infection by oxidative stress.