Extract of Cornus officinalis Protects Keratinocytes from Particulate Matter-induced Oxidative Stress.

The skin is one of the large organs in the human body and the most exposed to outdoor contaminants such as particulate matter < 2.5 µm (PM2.5). Recently, we reported that PM2.5 induced cellular macromolecule disruption of lipids, proteins, and DNA, via reactive oxygen species, eventually causing cellular apoptosis of human keratinocytes. In this study, the ethanol extract of Cornus officinalis fruit (EECF) showed anti-oxidant effect against PM2.5-induced cellular oxidative stress. EECF protected cells against PM2.5-induced DNA damage, lipid peroxidation, and protein carbonylation. PM2.5 up-regulated intracellular and mitochondrial Ca2+ levels excessively, which led to mitochondrial depolarization and cellular apoptosis. However, EECF suppressed the PM2.5-induced excessive Ca2+ accumulation and inhibited apoptosis. The data confirmed that EECF greatly protected human HaCaT keratinocytes from PM2.5-induced oxidative stress.

Particulate matter-induced senescence of skin keratinocytes involves oxidative stress-dependent epigenetic modifications.

Ambient air particulate matter (PM) induces senescence in human skin cells. However, the underlying mechanisms remain largely unknown. We investigated how epigenetic regulatory mechanisms participate in cellular senescence induced by PM with a diameter <2.5 (PM2.5) in human keratinocytes and mouse skin tissues. PM2.5-treated cells exhibited characteristics of cellular senescence. PM2.5 induced a decrease in DNA methyltransferase (DNMT) expression and an increase in DNA demethylase (ten-eleven translocation; TET) expression, leading to hypomethylation of the p16INK4A promoter region. In addition, PM2.5 led to a decrease in polycomb EZH2 histone methyltransferase expression, whereas the expression of the epigenetic transcriptional activator MLL1 increased. Furthermore, binding of DNMT1, DNMT3B, and EZH2 to the promoter region of p16INK4A decreased in PM2.5-treated keratinocytes, whereas TET1 and MLL1 binding increased, leading to decreased histone H3 lysine 27 trimethylation (H3K27Me3) and increased H3K4Me3 in the promoter of p16INK4A. PM2.5-induced senescence involved aryl hydrocarbon receptor (AhR)-induced reactive oxygen species (ROS) production. ROS scavenging dampened PM2.5-induced cellular senescence through regulation of DNA and histone methylation. Altogether, our work shows that skin senescence induced by environmental PM2.5 occurs through ROS-dependent the epigenetic modification of senescence-associated gene expression. Our findings provide information for the design of preventive and therapeutic strategies against skin senescence, particularly in light of the increasing problem of PM2.5 exposure due to air pollution.

Particulate Matter 2.5 Mediates Cutaneous Cellular Injury by Inducing Mitochondria-Associated Endoplasmic Reticulum Stress: Protective Effects of Ginsenoside Rb1.

The prevalence of fine particulate matter-induced harm to the human body is increasing daily. The aim of this study was to elucidate the mechanism by which particulate matter 2.5 (PM2.5) induces damage in human HaCaT keratinocytes and normal human dermal fibroblasts, and to evaluate the preventive capacity of the ginsenoside Rb1. PM2.5 induced oxidative stress by increasing the production of reactive oxygen species, leading to DNA damage, lipid peroxidation, and protein carbonylation; this effect was inhibited by ginsenoside Rb1. Through gene silencing of endoplasmic reticulum (ER) stress-related genes such as PERK, IRE1, ATF, and CHOP, and through the use of the ER stress inhibitor tauroursodeoxycholic acid (TUDCA), it was demonstrated that PM2.5-induced ER stress also causes apoptosis and ultimately leads to cell death; however, this phenomenon was reversed by ginsenoside Rb1. We also found that TUDCA partially restored the production of ATP that was inhibited by PM2.5, and its recovery ability was significantly higher than that of ginsenoside Rb1, indicating that the process of ER stress leading to cell damage may also occur via the mitochondrial pathway. We concluded that ER stress acts alone or via the mitochondrial pathway in the induction of cell damage by PM2.5, and that ginsenoside Rb1 blocks this process. Ginsenoside Rb1 shows potential for use in skin care products to protect the skin against damage by fine particles.

Eckol Inhibits Particulate Matter 2.5-Induced Skin Keratinocyte Damage via MAPK Signaling Pathway.

Toxicity of particulate matter (PM) towards the epidermis has been well established in many epidemiological studies. It is manifested in cancer, aging, and skin damage. In this study, we aimed to show the mechanism underlying the protective effects of eckol, a phlorotannin isolated from brown seaweed, on human HaCaT keratinocytes against PM2.5-induced cell damage. First, to elucidate the underlying mechanism of toxicity of PM2.5, we checked the reactive oxygen species (ROS) level, which contributed significantly to cell damage. Experimental data indicate that excessive ROS caused damage to lipids, proteins, and DNA and induced mitochondrial dysfunction. Furthermore, eckol (30 µM) decreased ROS generation, ensuring the stability of molecules, and maintaining a steady mitochondrial state. The western blot analysis showed that PM2.5 promoted apoptosis-related protein levels and activated MAPK signaling pathway, whereas eckol protected cells from apoptosis by inhibiting MAPK signaling pathway. This was further reinforced by detailed investigations using MAPK inhibitors. Thus, our results demonstrated that inhibition of PM2.5-induced cell apoptosis by eckol was through MAPK signaling pathway. In conclusion, eckol could protect skin HaCaT cells from PM2.5-induced apoptosis via inhibiting ROS generation.

Luteolin promotes apoptotic cell death via upregulation of Nrf2 expression by DNA demethylase and the interaction of Nrf2 with p53 in human colon cancer cells.

Luteolin, a dietary flavone, modulates various signaling pathways involved in carcinogenesis. In this study, we investigated the molecular mechanism that underlies the apoptotic effects of luteolin mediated by DNA demethylation of the nuclear factor erythroid 2-related factor 2 (Nrf2) promoter and the interaction of Nrf2 and p53, a tumor suppressor, in human colon cancer cells. Luteolin increased the expression of apoptosis-related proteins and antioxidant enzymes. In DNA methylation, luteolin inhibited the expression of DNA methyltransferases, a transcription repressor, and increased the expression and activity of ten-eleven translocation (TET) DNA demethylases, a transcription activator. Methyl-specific polymerase chain reaction and bisulfite genomic sequencing indicated that luteolin decreased the methylation of the Nrf2 promoter region, which corresponded to the increased mRNA expression of Nrf2. In addition, luteolin increased TET1 binding to the Nrf2 promoter, as determined using a chromatin immunoprecipitation (ChIP) assay. TET1 knockdown decreased the percentages of luteolin-treated cells in sub-G1 phase and cells with fragmented nuclei. Furthermore, complex formation between p53 and Nrf2 was involved in the apoptotic effects of luteolin. These results provide insight into the mechanism that underlies the anticancer effects of luteolin on colon cancer, which involve the upregulation of Nrf2 and its interaction with the tumor suppressor.

Diphlorethohydroxycarmalol Attenuates Fine Particulate Matter-Induced Subcellular Skin Dysfunction.

The skin, the largest organ in humans, is exposed to major sources of outdoor air pollution, such as fine particulate matter with a diameter ≤ 2.5 µm (PM2.5). Diphlorethohydroxycarmalol (DPHC), a marine-based compound, possesses multiple activities including antioxidant effects. In the present study, we evaluated the protective effect of DPHC on PM2.5-induced skin cell damage and elucidated the underlying mechanisms in vitro and in vivo. The results showed that DPHC blocked PM2.5-induced reactive oxygen species generation in human keratinocytes. In addition, DPHC protected cells against PM2.5-induced DNA damage, endoplasmic reticulum stress, and autophagy. HR-1 hairless mice exposed to PM2.5 showed lipid peroxidation, protein carbonylation, and increased epidermal height, which were inhibited by DPHC. Moreover, PM2.5 induced apoptosis and mitogen-activated protein kinase (MAPK) protein expression; however, these changes were attenuated by DPHC 5. MAPK inhibitors were used to elucidate the molecular mechanisms underlying these actions, and the results demonstrated that MAPK signaling pathway may play a key role in PM2.5-induced skin damage.

Norgalanthamine Stimulates Proliferation of Dermal Papilla Cells via Anagen-Activating Signaling Pathways.

Norgalanthamine has been shown to possess hair-growth promoting effects, including increase in hair-fiber length in cultured rat vibrissa follicles and increase in dermal papilla cell (DPC) proliferation. However, the intracellular mechanisms that underlie the action of norgalanthamine in DPCs have not been investigated. In this study, we addressed the ability of norgalanthamine to trigger anagen-activating signaling pathways in DPCs. Norgalanthamine significantly increased extracellular signal-regulated kinase (ERK) 1/2 phosphorylation at 0.1 µM, a concentration at which DPC proliferation was also induced. Furthermore, the increases in norgalanthamine-induced ERK 1/2 activation and subsequent DPC proliferation were suppressed by the mitogen-activated protein kinase/ERK kinase (MEK) 1/2 inhibitor, U0126. A 0.1 µM dose of norgalanthamine also increased phosphorylation of AKT, which was followed by an increase in glycogen synthase kinase 3ß phosphorylation and nuclear translocation of ß-catenin. In addition, LY294002, a phosphatidylinositol 3 kinase (PI3K) inhibitor, blocked the effect of norgalanthamine on DPC proliferation. These results suggest that norgalanthamine can stimulate the anagen phase of the hair cycle in DPCs via activation of the ERK 1/2, PI3K/AKT, and Wnt/ß-catenin pathways.

Purpurogallin Protects Keratinocytes from Damage and Apoptosis Induced by Ultraviolet B Radiation and Particulate Matter 2.5.

Purpurogallin, a natural phenol obtained from oak nutgalls, has been shown to possess antioxidant, anticancer, and anti-inflammatory effects. Recently, in addition to ultraviolet B (UVB) radiation that induces cell apoptosis via oxidative stress, particulate matter 2.5 (PM2.5) was shown to trigger excessive production of reactive oxygen species. In this study, we observed that UVB radiation and PM2.5 severely damaged human HaCaT keratinocytes, disrupting cellular DNA, lipids, and proteins and causing mitochondrial depolarization. Purpurogallin protected HaCaT cells from apoptosis induced by UVB radiation and/or PM2.5. Furthermore, purpurogallin effectively modulates the pro-apoptotic and anti-apoptotic proteins under UVB irradiation via caspase signaling pathways. Additionally, purpurogallin reduced apoptosis via MAPK signaling pathways, as demonstrated using MAPK-p38, ERK, and JNK inhibitors. These results indicate that purpurogallin possesses antioxidant effects and protects cells from damage and apoptosis induced by UVB radiation and PM2.5.

7,8-Dihydroxyflavone Protects High Glucose-Damaged Neuronal Cells against Oxidative Stress.

Oxidative stress is considered a major contributor in the pathogenesis of diabetic neuropathy and in diabetes complications, such as nephropathy and cardiovascular diseases. Diabetic neuropathy, which is the most frequent complications of diabetes, affect sensory, motor, and autonomic nerves. This study aimed to investigate whether 7,8-dihydroxyflavone (7,8-DHF) protects SH-SY5Y neuronal cells against high glucose-induced toxicity. In the current study, we found that diabetic patients exhibited higher lipid peroxidation caused by oxidative stress than healthy subjects. 7,8-DHF exhibits superoxide anion and hydroxyl radical scavenging activities. High glucose-induced toxicity severely damaged SH-SY5Y neuronal cells, causing mitochondrial depolarization; however, 7,8-DHF recovered mitochondrial polarization. Furthermore, 7,8-DHF effectively modulated the expression of pro-apoptotic protein (Bax) and anti-apoptotic protein (Bcl-2) under high glucose, thus inhibiting the activation of caspase signaling pathways. These results indicate that 7,8-DHF has antioxidant effects and protects cells from apoptotic cell death induced by high glucose. Thus, 7,8-DHF may be developed into a promising candidate for the treatment of diabetic neuropathy.

Particulate matter induces inflammatory cytokine production via activation of NFκB by TLR5-NOX4-ROS signaling in human skin keratinocyte and mouse skin.

Particulate matter (PM) increases levels of pro-inflammatory cytokines, but its effects on the skin remain largely unknown. We investigated the signal transduction pathway and epigenetic regulatory mechanisms underlying cellular inflammation induced by PM with a diameter of ≤ 2.5 (PM2.5) in vitro and in vivo. PM2.5-treated skin keratinocytes produced various inflammatory cytokines, including IL-6. The binding of PM2.5 to TLR5 initiated intracellular signaling through MyD88, and led to the translocation of NFκB to the nucleus, where it bound the NFκB site within IL-6 promoter. Furthermore, PM2.5 induced a direct interaction between TLR5 and NOX4, and in turn induced the production of ROS and activated NFκB-IL-6 downstream, which was prevented by siRNA-mediated knockdown of NOX4 or antioxidant treatment. Furthermore, expression of TLR5, MyD88, NOX4, phospho-NFκB, and IL-6 was increased in skin tissue of PM2.5-treated flaky tail mice. PM2.5-induced increased transcription of IL-6 was regulated via DNA methylation and histone methylation by epigenetic modification; the binding of DNA demethylase and histone methyltransferase to the IL-6 promoter regions resulted in increased IL-6 mRNA expression. Our findings provide deep insight into the pathogenesis of PM2.5 exposure and can be used as a therapeutic strategy to treat inflammatory skin diseases caused by PM2.5 exposure.

Particulate matter 2.5 damages skin cells by inducing oxidative stress, subcellular organelle dysfunction, and apoptosis.

The skin is the largest organ of the human body and the one mostly exposed to outdoor contaminants. To evaluate the biological mechanisms underlying skin damage caused by fine particulate matter (PM2.5), we analyzed the effects of PM2.5 on cultured human keratinocytes and the skin of experimental animals. PM2.5 was applied to human HaCaT keratinocytes at 50 µg/mL for 24 h and to mouse skin at 100 µg/mL for 7 days. The results indicate that PM2.5 induced oxidative stress by generating reactive oxygen species both in vitro and in vivo, which led to DNA damage, lipid peroxidation, and protein carbonylation. As a result, PM2.5 induced endoplasmic reticulum stress, mitochondrial swelling, and autophagy, and caused apoptosis in HaCaT cells and mouse skin tissue. The PM2.5-induced cell damage was attenuated by antioxidant N-acetyl cysteine, confirming that PM2.5 cellular toxicity was due to oxidative stress. These findings contribute to understanding of the pathophysiological mechanisms triggered in the skin by PM2.5, among which oxidative stress may play a major role.

3-Bromo-4,5-dihydroxybenzaldehyde Enhances the Level of Reduced Glutathione via the Nrf2-Mediated Pathway in Human Keratinocytes.

A natural bromophenol found in seaweeds, 3-bromo-4,5-dihydroxybenzaldehyde (BDB), has been shown to possess antioxidant effects. This study aimed to investigate the mechanism by which BDB protects skin cells subjected to oxidative stress. The effect of BDB on the protein and mRNA levels of glutathione-related enzymes and the cell survival of human keratinocytes (HaCaT cells) was investigated. BDB treatment increased the protein and mRNA levels of glutathione synthesizing enzymes and enhanced the production of reduced glutathione in HaCaT cells. Furthermore, BDB activated NF-E2-related factor 2 (Nrf2) and promoted its localization into the nucleus by phosphorylating its up-stream signaling proteins, extracellular signal-regulated kinase and protein kinase B. Thus, BDB increased the production of reduced glutathione and established cellular protection against oxidative stress via an Nrf2-mediated pathway.

The Red Algae Compound 3-Bromo-4,5-dihydroxybenzaldehyde Protects Human Keratinocytes on Oxidative Stress-Related Molecules and Pathways Activated by UVB Irradiation.

Skin exposure to ultraviolet B (UVB) irradiation leads to the generation of reactive oxygen species (ROS). Excessive ROS cause aging of the skin via basement membrane/extracellular matrix degradation by matrix metalloproteinases (MMPs). We recently demonstrated that 3-bromo-4,5-dihydroxybenzaldehyde (BDB), a natural compound of red algae, had a photo-protective effect against UVB-induced oxidative stress in human keratinocytes. The present study focused on the effect of BDB on UVB-irradiated photo-aging in HaCaT keratinocytes and the underlying mechanism. BDB significantly impeded MMP-1 activation and expression, and abrogated the activation of mitogen-activated protein kinases and intracellular Ca2+ level in UVB-irradiated HaCaT cells. Moreover, BDB decreased the expression levels of c-Fos and phospho-c-Jun and the binding of activator protein-1 to the MMP-1 promoter induced by UVB irradiation. These results offer evidence that BDB is potentially useful for the prevention of UVB-irradiated skin damage.

Phloroglucinol enhances the repair of UVB radiation-induced DNA damage via promotion of the nucleotide excision repair system in vitro and in vivo.

Exposure to solar UVB radiation can lead to the formation of DNA lesions such as cyclobutane pyrimidine dimers (CPDs). Nucleotide excision repair (NER) is critical for the repair of CPDs induced by UV radiation. The purpose of this study was to investigate the ability of phloroglucinol to protect against the formation of UVB-induced CPDs in vitro and in vivo. Exposure to UVB radiation increased the number of CPDs in both HaCaT keratinocytes and mouse skin; however, these increases were reduced by treatment with phloroglucinol. Expression levels of xeroderma pigmentosum complementation group C (XPC) and excision repair cross-complementation 1 (ERCC1), which are essential components of the NER pathway, were reduced following UVB exposure, although phloroglucinol treatment recovered these levels in both HaCaT keratinocytes and mouse skin. Phloroglucinol also inhibited UVB-induced reductions in binding of the transcription factors specificity protein 1 to the XPC promoter. These results demonstrate that phloroglucinol can protect cells against UVB-induced DNA damage by inducing NER.

Phloroglucinol inhibits ultraviolet B radiation-induced oxidative stress in the mouse skin.

PURPOSE: Previously we demonstrated that phloroglucinol (1,3,5-trihydroxybenzene) protected human HaCaT keratinocytes against ultraviolet B (UVB, 280-320 nm)-induced oxidative stress in vitro by scavenging intracellular reactive oxygen species (ROS). The current study investigated whether phloroglucinol could similarly protect the mouse skin against UVB-induced oxidative tissue damage in vivo. MATERIALS AND METHODS: Male 7-week-old Balb/c mice were divided into the following untreated normal control, phloroglucinol only-treated, vehicle plus UVB (30 or 60 mJ/cm(2))-exposed, and phloroglucinol (10 or 50 mg/ml) plus UVB (30 or 60 mJ/cm(2))-treated groups. Following UVB exposure, phloroglucinol or phosphate buffered saline vehicle was applied to the dorsal skin of each mouse daily for 3 days. Studies were conducted at 24 h after the last of the UVB exposures. Histopathological analyses of dorsal skin lesions were performed on all mice. In addition, the levels of UVB-provoked injury to cellular components, including DNA, proteins, and lipids were detected by levels of 8-oxoguanine (8-oxoG), protein carbonyls, and 8-isoprostane. Apoptosis were assessed by using western blot for B-cell lymphoma-2-associated X protein (Bax) and activated caspase-3 expression, by using immunohistochemistry. RESULTS: UVB radiation increased the thickness of the epidermis and the dermis, and also stimulated the accumulation of mast cells in the irradiated skin. However, treatment with phloroglucinol significantly decreased all of these parameters. Furthermore, phloroglucinol decreased UVB-provoked injury to cellular components, including DNA, proteins, and lipids; down-regulated the expression of phospho-histone H2A.X in the injured skin; and reduced the UVB-generated levels of 8-oxoG, protein carbonyls, and 8-isoprostane, which are all markers of oxidative stress. In addition, phloroglucinol attenuated the UVB-induced expression of the pro-apoptotic proteins, Bax protein, and activated caspase-3. CONCLUSION: These results suggest that phloroglucinol safeguards the mouse skin against UVB-induced oxidative stress and apoptosis.

Evidence-based practice for pain management for cancer patients in an acute care setting.

The purpose of this study is to implement an evidence utilization project using an audit and feedback approach to improve cancer pain management. A three-phased audit and feedback approach was used. A 46-bed oncology nursing unit in the university's cancer centre was selected as a research site. Nursing records extracted from 137 patients (65 for the baseline assessment and 72 for the follow-up audit) were used to examine nurse compliance with four audit criteria derived from best practice guidelines related to the assessment and management of pain. We observed a significant improvement in compliance from baseline to follow-up for the following criteria: documenting the side effects of opioids (2-83%), use of a formalized pain assessment tool (22-75%), and providing education for pain assessment and management to patients and caregivers (0-47%). The audit and feedback method was applicable to the implementation of clinical practice guidelines for cancer pain management. Leadership from both administrative personnel and staff nurses working together contributes to the spread of an evidence-based practice culture in clinical settings. As it was conducted in a single oncology nursing unit and was implemented over a short period of time, the results should be carefully interpreted.

Implementation of best practice for chemotherapy-induced nausea and vomiting in an acute care setting.

BACKGROUND: Chemotherapy-induced nausea and vomiting is the commonest side-effect for patients undergoing cancer treatment with chemotherapy. These symptoms can lead to nutritional deficiencies, dehydration and electrolyte imbalance, and negative impacts on quality of life. However, wide gaps exist between clinician and patient perceptions of nausea and vomiting. Effective communication about these symptoms is essential for proper treatment. We conducted a recent chart review to identify gaps in practice regarding chemotherapy-induced nausea and vomiting assessment and documentation. AIM: The goal of this project was to improve local practice in the management of chemotherapy-induced nausea and vomiting in patients with cancer. METHODS: This study used one pre- and two post-implementation audit strategies utilising the Joanna Briggs Institute Practical Application of Clinical Evidence System (JBI-PACES) and Getting Research into Practice (GRiP) module. The study was conducted in the 33-bed oncology ward of a large acute care hospital in Korea from February 2010 to June 2010. To facilitate evidence-based nursing practice, audit-feedback-re-audit cycles strategies were used. The audits included four criteria recommended by the Joanna Briggs Institute. RESULTS: There were statistically significant improvements in all four criteria. The first post-implementation audit showed that all four audit criteria rated >50% in compliance. At the second follow-up audit, all four audit criteria rated 100% compliance, indicating excellent compliance with best practice. The differences between the pre- and post-data were statistically significant (P < 0.001) for all four audit criteria. CONCLUSIONS: The results indicate that the pre- and post-implementation audits are an effective method in improvement of assessment, documentation and evidence-based nursing implementation for cancer symptom management.

p53 and cell-cycle-regulated protein expression in small intestinal cells after fast-neutron irradiation in mice.

The involvement of the p53 gene in apoptosis of many cell types towards y-radiation is well established. However, little information is available on the relationship between p53 status and cells' ability to undergo apoptosis following exposure to fast neutrons. The aim of this study was to characterize the apoptotic pathway traveled by neutrons in mouse intestinal crypt cells. Each mouse received whole body doses of 0.25-8 Gy fast neutrons and were sacrificed 0, 4, 6, 12, 24, 48, and 72 h, respectively, after irradiation. Apoptosis of crypt cells and expression of p53, cyclin A, cyclin B, cyclin D, and cyclin E were measured. The apoptosis in crypt cells was maximal at 4 and 6 h after irradiation, showing a gradual decline at 24 h. The highest frequency of apoptosis was seen at a 1 Gy dose and then declined gradually beyond a 2 Gy dose with high levels of damage. In immunoblot analysis, apoptosis was confirmed to be dependent on p53 function after fast-neutron irradiation. In addition, cyclin B1, cyclin D, and cyclin E were overexpressed in intestinal cells after fast-neutron irradiation and their immunoreactivities were increased strongly in round and oval cells of laminar propria in villi core and crypts. The results of the current study suggest that apoptosis in crypt cells shows a time- and dose-dependent increase after fast-neutron irradiation. In addition, fast-neutron-induced apoptosis in mouse intestinal crypt cells appears to be related to the increase in functional p53 proteins to a level sufficient to initiate apoptosis and up-regulation of cell-cycle-regulated proteins, which may lead to resistance to DNA damage through cell cycle arrest, is involved deeply in protection of gastrointestinal cells after low doses of fast-neutron irradiation.

Activation of embryonic intermediate filaments contributes to glial scar formation after spinal cord injury in rats.

The expression of two intermediate filaments, nestin and vimentin, was studied in spinal cord injury (SCI) to elucidate their roles in the formation of glial scars. Rats were sacrificed 1, 4, and 7 days after induction of compression injury of the spinal cord using an aneurysm clip. The affected spinal cords were studied using antibodies against nestin and vimentin intermediate filaments. One day after spinal cord injury, some clusters of nestin-positive vessels were detected in the center of the injury, but few were seen in other cell types. Vimentin immunostaining was detected in some glial cells in the center and its level of immunoreactivity was enhanced in the ependymal cells of the central canal. On days 4 and 7 after spinal cord injury, astrocytes and some ependymal cells in the central canal were stained positively for nestin and increased expression of nestin was observed in vessels. Vimentin was detected in some macrophages and astrocytes in the lesions. Nestin was co-localized with glial fibrillary acidic protein in some glial cells in SCI. These findings imply that spinal cord cells in adult animals have embryonic capacity, and these cells are activated after injury, which in turn contributes to repair of spinal cord injury through formation of a glial scar.

Histochemical detection of glycoconjugates in the male reproductive system of the horse.

Lectins are glycoproteins of plant and animal origin that have the ability to bind specific carbohydrate residues of cell glycoconjugates, particularly in terminal positions. In this study, the binding of lectins, Dolichos biflorus agglutinin (DBA), soybean agglutinin (SBA), Bandeiraea simplicifolia BS-1 (isolectin B4), Triticum vulgaris (WGA), Arachis hypogaea (PNA), and Ulex europaeus (UEA-I), was studied in the reproductive systems of male thoroughbred horses.DBA was detected in the stereocilia of the caput and corpus epididymis, and in the vas deferens. It was weakly detected in connective tissue of the corpus epididymis. Strong SBA staining was seen in epithelial cells in the testis, stereocilia of the corpus and cauda epididymis, and in the vas deferens. There were intense positive reactions for isolectin B4 in interstitial cells in all tissue and serosa of the vas deferens. PNA staining was seen only in stereocilia in the caput and corpus epididymis, and in the vas deferens. Strong WGA staining was seen throughout the testis, except in Sertoli cells, stereocilia, and connective tissue. UEA-I was detected in secondary spermatids, stereocilia, and epithelial cells of the cauda epididymis. These results show that degenerating cells in the testis, epididymal tubules, and vas deferens have differential affinities for lectins, and suggest that lectins play a role in the reproductive system of the horse. The heterogeneity of the lectin staining pattern in the reproductive tubules of adult horses suggests that the carbohydrate composition of each cell type is region specific.