Transplantation of bone marrow stromal cells (MSCs) has been regarded as a potential approach for promoting nerve regeneration. In the present study, we investigated the influence of MSCs on spinal cord neurosphere cells in vitro and on the regeneration of injured spinal cord in vivo by grafting. MSCs from adult rats were cocultured with fetal spinal cord-derived neurosphere cells by either cell mixing or making monolayered-feeder cultures. In the mixed cell cultures, neuroshpere cells were stimulated to develop extensive processes. In the monolayered-feeder cultures, numerous processes from neurosphere cells appeared to be attracted to MSCs. In an in vivo experiment, grafted MSCs promoted the regeneration of injured spinal cord by enhancing tissue repair of the lesion, leaving apparently smaller cavities than in controls. Although the number of grafted MSCs gradually decreased, some treated animals showed remarkable functional recovery. These results suggest that MSCs might have profound effects on the differentiation of neurosphere cells and be able to promote regeneration of the spinal cord by means of grafting.

Freeze-dried alginate sponge cross-linked with covalent bonds has been demonstrated to enhance nerve regeneration in peripheral nerves and spinal cords. The present study examined, at early stages after surgery, the outgrowth of regenerating axons and reactions of astrocytes at the stump of transected spinal cord in young rats. Two segments (Th7-8) were resected, and alginate was implanted in the lesion. As controls, collagen gel was implanted in place of alginate or the lesion was left without implantation. Two and 4 weeks after surgery, nerve outgrowth and astrocyte reactions were examined. Many regenerating axons, some of which were accompanied by astrocytic processes, were found to extend from the stump into the alginate-implanted lesion. In the all nonimplanted animals, large cystic cavities were formed at both interfaces with no definite axonal outgrowth into the lesion. In collagen-implanted animals, cavity formation was found in some rats, and regenerating axons once formed at the stumps did not extend further into the lesion. Astrocytic processes extending into alginate-implanted lesion had no basal laminae, whereas those found in control experiments were covered by basal laminae. These findings suggest that alginate contributed to reducing the barrier composed of connective tissues and reactive astrocytic processes, and served as a scaffold for the outgrowth of regenerating axons and elongation of astrocytic processes.

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Neurospheres were obtained by culturing hippocampal cells from transgenic rat fetuses (E16) expressing green fluorescent protein (GFP). The neurosphere cells were injected into the cerebrospinal fluid (CSF) through the 4th ventricle of young rats (4 weeks old) that had been given a contusion injury at T8 -9 of the spinal cord. The injected neural stem cells were transported through the CSF to the spinal cord, attached to the pial surface at the lesion, and invaded extensively into the spinal cord tissue as well as into the nerve roots. The grafted stem cells survived well in the host spinal cord for as long as 8 months after transplantation. Immunohistochemical study showed that many grafted stem cells had differentiated into astrocytes at 1-4 months, and some into oligodendrocytes at 8 months postoperatively. Immunoelectron microscopy showed that the grafted stem cells were well integrated into the host tissue, extending their processes around nerve fibers in the same manner as astrocytes. In addition, grafted stem cells within nerve roots closely surrounded myelinated fibers or were integrated into unmyelinated fiber bundles; those associated with myelinated fibers formed basal laminae on their free surface, whereas those associated with unmyelinated fibers were directly attached to axons and Schwann cells, indicating that grafted stem cells behaved like Schwann cells in the nerve roots.

Our daily exposure to ultraviolet radiation (UVR) results in the production of reactive oxygen species (ROS), lipids, proteins and DNA damage and alteration in fibroblast structure, thus contributing to skin photoaging. For this reason, the use of natural bioactive compounds with antioxidant activity could be a strategic tool to overcome ultraviolet A (UV-A) induced deleterious effect. Neferine is an alkaloid extract from the seed embryos of lotus (Nelumbo nucifera Gaertn). In the present study, we report the protective effect of neferine against UV-A induced oxidative stress and photoaging in human dermal fibroblasts (HDFs). HDFs subjected to UV-A irradiation showed increased production of ROS and malondialdehyde (MDA). Furthermore, it depleted the cellular enzymatic antioxidant superoxide dismutase (SOD) and non-enzymatic antioxidant glutathione peroxidase (GPx). On the other hand, HDFs treated with neferine followed by UV-A irradiation reversed the process, reduced the ROS and lipid peroxidation and restored the antioxidants pool. Moreover, neferine treatment significantly inhibited UV-A induced matrix metalloproteinase-1 (MMP-1) expression in HDFs. Remarkable morphological and ultrastructural alterations observed in HDFs upon UV-A irradiation, were also reduced with neferine treatment. Taken together, our results suggest that neferine has strong antioxidative and photoprotective properties and thus may be a potential agent for the prevention and treatment of UV-A mediated skin photoaging.

The aim of the present study was to evaluate the anti-photoaging effect of neferine upon exposure of mice to ultraviolet (UV) radiation. An in vivo photoaging model was established by repeatedly exposing mouse dorsal skin to UV-A and UV-B radiation for 12 weeks. Through skin photographs, hematoxylin and eosin staining, Masson's trichrome staining, and scanning and transmission electron microscopy, skin wrinkles, epidermal thickness and dermal collagen were analyzed in the UV-irradiated mouse skin. Furthermore, the levels of endogenous antioxidants, namely superoxide dismutase (SOD) and glutathione peroxidase (GPx), were measured to determine the extent of UV-induced oxidative stress that was associated with photoaging. The results demonstrated that the topical application of neferine following UV irradiation reduced oxidative stress by increasing SOD and GPx activities, and attenuated the photoaging process. Histological and ultrastructural examination revealed that neferine delayed skin wrinkle formation by inhibiting epidermal hypertrophy and collagen loss and degradation. In conclusion, the results of the present study indicated that neferine effectively prevents UV-induced skin photoaging and photodamage.

Epithelioid hemangioendotheliomas are unique vascular tumors characterized by epithelioid or histiocytoid endothelial cells that mainly affect adults. This low-grade malignant vascular tumor was described as a distinctive condition in 1982 by Weiss and Enzinger. Although the tumor is classified in between an angiolymphoid hyperplasia with eosinophilia and an epithelioid angiosarcoma, it sometimes takes a clinical course resembling that of angiosarcoma. We describe that case of a 12-year-old boy who presented with an approximately 6-month history of a spontaneous chronic lesion in his right armpit and became a painful ulceration in the prior 2-month period. The histopathologic examination revealed small nests and cords of spindling epithelioid endothelial cells, intracytoplasmic lumina containing erythrocytes, pinocytotic vesicles and a necrotic area. Immunohistochemical staining was positive for the endothelial markers CD31, CD34, CK(+), and vim(+). On the basis of these findings the diagnosis of EHE was made. After surgery, pathologic examination revealed metastasis in the lymph nodes. So polychemotherapy was started. As our case report shows, it is possibility that cutaneous ulceration of a malignant tumor such as EHE should be considered, even in children.

Taken together, our results suggest that neferine can prevent UV-B-induced oxidative damage and may thus be a potential agent for prevention and treatment of skin damage and photoaging.