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This study was conducted to demonstrate whether puerarin regulates glutamine synthetase (GS) activity following intraocular hypertension and has therapeutic potential in ophthalmology for the protection of optic nerves in patients with glaucoma. This study used a Wistar rat model of acute closed-angle glaucoma to investigate the effect of puerarin on GS activity in rat retina following intraocular hypertension. Acute intraocular hypertension was induced by increasing anterior chamber pressure to 110 mmHg for 30 min in the left eyes of 50 Wistar rats, while 5 additional Wistar rats lacking intraocular hypertension were used as a control group. Retinal GS activity was measured at 4, 12, 24, 36 and 72 h after induction of acute intraocular hypertension with/without puerarin treatment. Compared to the control group that lacked intraocular hypertension, GS activity in the intraocular hypertension group significantly decreased at 4 and 12 h (P

Background: CD105 is highly expressed on human activated endothelial cells (ECs), is an important component of the TGF-β1 receptor complex and is essential for angiogenesis. CD105 expression is up-regulated in activated ECs and is an important potential marker for cancer prognosis. Materials and Methods: In vitro rat myoblasts transfected with the L-CD105 and S-CD105 transfectants. The transfectants were treated with TGF-β1 for the angiogenesis study. Results: L-CD105 affects cell proliferation in the presence and absence of TGF-β1, and inhibits p-ERK1/2, p-MEK1/2 and p-c-Jun in L-CD105 transfectants compared to controls. The induction of phospho-ERK1/2 following treatment with TGF-β1 remained significantly lower in L-CD105 transfectants compared to controls. Conclusion: L-CD105 inhibits the phosphorylation of ERK1/2, MEK1/2, c-Jun1/2/3, and associated signalling intermediates. CD105 modulates cell growth and TGF-β1 induced cell signalling through ERK-c-Jun expression.

Knowledge of changes in macrophages following bacterial engulfment is limited. U937-derived macrophages were incubated with Staphylococcus aureus or Pseudomonas aeruginosa. Morphological and biochemical changes in macrophages following host-pathogen interactions were visualized using Scanning Electron Microscopy (SEM) and Fourier-Transform Infrared Spectroscopy (FTIR) respectively. Principal Component Analysis (PCA) was used to assess the variability in the FTIR spectra. Following host-pathogen interactions, survival of S. aureus was significantly lower than P. aeruginosa (P 99 % of variability in the FTIR spectra explained by the first two principal components. These findings demonstrated that there were clear morphological and biochemical changes in macrophages following engulfment of two different bacterial types suggesting that the biochemical components of the bacterial cell wall influenced the biochemical characteristics and hence the morphology of macrophages in distinct ways.

Cereal derived arabinoxylans (AXs) are non-starch polysaccharides that have immunomodulatory activities. These activities are thought to be related to the low molecular weight fractions of AXs. Wheat and wheat byproducts are rich in AXs, however, the water extractable fraction of AXs in wheat products is low. Water extraction of AXs can be improved by extrusion processing, which increases the extractability of the water soluble fraction. The aim of this study was to determine the extractability and molecular weight of the water soluble fraction of AXs from wheat endosperm after extrusion at screw speeds of 80 and 160 rpm. Extrusion processing significantly (P < 0.05) increased the water extractability of AXs in a screw-speed dependent manner (13.07 ± 0.12% at 80 rpm and 15.45 ± 0.16% at 160 rpm compared to 8.95 ± 0.10% in the non-extruded control) due to a significant increase (P < 0.05) in low molecular weight fractions of AXs in extruded samples.

Arabinoxylans (AXs) are major dietary fibre in cereals. Recently, AXs have attracted a great deal of attention because of their biological activities. These activities have been suggested to be related to the content of low molecular weight (Mw) AXs, in particular those with Mw below 32 kDa. Rice bran is a rich source of AXs. However, water extraction of AXs is difficult and often gives low yield. Extrusion processing has been used to increase the solubility of cereal dietary fibre. The aim of this research was to study the effect of extrusion screw-speeds (80 and 160) rpm on the extraction yield and Mw of water extractable AXs from rice bran. It was found that the extraction of AXs increased significantly with an increase in screw speed and was accompanied by a significant decrease in the Mw of AXs from extruded rice bran. The percentage of very low molecular weight AXs (0.79–1.58 kDa) significantly increased with increasing screw speed.

Inflammation is regulated by many endogenous factors including estrogen, a steroid hormone that declines with increasing age, leading to excessive inflammation in the elderly. C-reactive protein (CRP) is an acute phase inflammatory protein that exists in two forms, native CRP (nCRP) and monomeric CRP (mCRP), which mediate distinct biological activities. It is unclear how each CRP isoform mediates nitric oxide (NO), a signaling molecule generated by NO synthase (NOS). This study investigated whether CRP isoforms have distinct effects on NO production by unstimulated and lipopolysaccharide (LPS)-activated monocytes/macrophages and whether estrogen mediates CRP-induced NO production in an in vitro model of aging. NO and inducible NOS (iNOS) were measured (n = 12) by the Griess assay and an enzyme-linked immunosorbent assay, respectively following incubation (24 h) of human-derived U937 monocytes/macrophages with CRP isoforms [(nCRP) = 500 and 1,000 µg/ml; (mCRP) = 100 and 250 µg/ml] in the absence or presence of 17 beta-estradiol (1 × 10−7, 1 × 10−8, and 1 × 10−9 M). The response to each CRP isoform and estrogen was dependent on the differentiation and activation status of cells. Monocytes with or without prior LPS-activation significantly increased (P 0.05) on NO/iNOS production by unactivated or LPS-activated macrophages, whereas nCRP significantly (P

The immunomodulatory activity of the arabinoxylans (AXs) extracts from cereal sources has beenreported to impart health benefits in terms of immune enhancement. This study investigated the effect ofenzymatic extraction on extraction yield and structure of AXs from wheat flour pentosan fraction. Underthe optimised conditions, the extraction yield of AXs reached up to 81.25%. Furthermore, the studydetermined whether water-extracted AXs (WEAXs) and enzyme-extracted AXs (E-WEAXs) from wheatflour were able to differentially stimulate nitric oxide (NO) secretion through increased levels of induciblenitric oxide synthase (iNOS) in human U937 monocytes. The results indicated that AXs concomitantlyinduced (P < 0.05) both NO and iNOS productions in U937 monocytes compared to untreated cells.Compared with WEAXs, E-WEAXs resulted in a higher proportion of low Mw (1– 10 KDa) AXs(49.51% vs. 19.11% in WEAXs), a higher A/X ratio (0.83 vs. 0.48 in WEAXs) and a higher yield(12.83  0.35% vs. 7.54  0.47% in WEAXs). Moreover, E-WEAXs induced significantly (P < 0.05)greater NO and iNOS production per million viable cells (61.8  2.7 lM and 42.41  3.83 ng respec-tively) than WEAXs (51.6  2.6 lM and 33.46  1.48 ng, respectively). The findings suggest AXs mayheighten innate immune activity in the absence of infection or disease through an iNOS-mediated stimula-tion of NO production. The immunomodulatory activity of the wheat-derived AXs was enhanced byenzyme treatment, with low Mw and high A/X ratio associated with elevated NO/iNOS levels in humanmonocytes compared to water extraction.

Angiotensin converting enzyme (ACE) and bradykinin receptor B2 (B2R) genetic variation may affect thirst because of effects on angiotensin II production and bradykinin activity, respectively. To examine this, 45 healthy Caucasian men completed 60 min of cycle exercise at 62% ± 5% peak oxygen uptake in a room heated to 30.5 ± 0.3 °C with ad libitum fluid intake. Blood samples were collected pre-, mid-, and immediately post-cycle. Fluid intake, body mass loss (BML), sweat loss (determined via changes in body mass and fluid intake), and thirst sensation were recorded. All participants were genotyped for the ACE insert fragment (I) and the B2R insert sequence (P). Participants were homozygous for the wild-type allele (WW or MM), heterozygous (WI or MP) or homozygous for the insert (II or PP). No differences between genotype groups were found in mean (±SD) voluntary fluid intake (WW: 613 ± 388, WI: 753 ± 385, II: 862 ± 421 mL, p = 0.31; MM: 599 ± 322, MP: 745 ± 374, PP: 870 ± 459 mL, p = 0.20), percentage BML or any other fluid balance variables for both the ACE and B2R genes, respectively. Mean thirst perception in the B2R PP group, however, was higher (p < 0.05) than both MM and MP at 30, 45, and 60 min. In conclusion, the results of this study suggest that voluntary fluid intake and fluid balance in healthy men performing 60 min of moderate-intensity exercise in the heat are not predominantly influenced by ACE or B2R genetic variation.

Arabinoxylans (AXs) are major dietary fibers. They are composed of backbone chains of β-(1-4)-linked xylose residues to which α-l-arabinose are linked in the second and/or third carbon positions. Recently, AXs have attracted a great deal of attention because of their biological activities such as their immunomodulatory potential. Extraction of AXs has some difficulties; therefore, various methods have been used to increase the extractability of AXs with varying degrees of success, such as alkaline, enzymatic, mechanical extraction. However, some of these treatments have been reported to be either expensive, such as enzymatic treatments, or produce hazardous wastes and are non-environmentally friendly, such as alkaline treatments. On the other hand, mechanical assisted extraction, especially extrusion cooking, is an innovative pre-treatment that has been used to increase the solubility of AXs. The aim of the current review article is to point out the health-related effects and to discuss the current research on the extraction methods of AXs.

© 2016 American Chemical Society. The ingestion of foods and food-derived substances that may mediate the immune system is widely studied. Evidence suggests cereal arabinoxylans (AXs) have immunomodulatory activities that may impart health benefits in terms of immune enhancement. This study extracted AXs from corn bran using alkali and developed a modification process using three endoxylanases to obtain fractions of lower molecular weight ranges. In vitro studies showed extracted and modified AXs significantly (P < 0.05) elevated nitric oxide (NO) synthesis by the human U937 monocytic cell line (ranging from 53.7 ± 1.1 to 62.9 ± 1.2 μM per million viable cells) at all concentrations tested (5-1000 μg/mL), indicative of immune enhancement compared to an untreated control (43.7 ± 1.9 μM per million viable cells). The study suggested the dose range and Mw distribution of AXs are key determinants of immune-modulatory activity. AXs in the low Mw range (0.1-10 KDa) were the most effective at inducing NO secretion by U937 macrophages at low AX concentration ranges (5-50 μg/mL), with NO production peaking at 62.9 ± 1.2 μM per million viable cells with 5 μg/mL of AX (P = 0.0009). In contrast, AXs in the high Mw range (100-794 kDa) were most effective at inducing NO at high AX concentration ranges (500-1000 μg/mL) with NO production reaching a maximum of 62.7 ± 1.3 μM per million viable cells at 1000 μg/mL of AX (P = 0.0011). The findings suggest that dietary AXs from corn bran may heighten innate immune responses in the absence of infection or disease.

Sodium butyrate (NaBu), a form of short-chain fatty acid (SCFA), acts classically as a potent anti-angiogenic agent in tumour angiogenesis models, some authors demonstrated that low concentrations of NaBu may contribute to healing of tendon-bone injury in part at least through promotion of tissue remodelling. Here, we investigated the effects of low-range concentrations of NaBu using in vitro and in vivo assays using angiogenesis as the primary outcome measure and the mechanisms through which it acts. We demonstrated that NaBu, alone or perfused from the UltraBraid+NaBu suture was pro-angiogenic at very low-range doses promoting migration, tube formation and cell invasion in bovine aortic endothelial cells (BAECs). Furthermore, cell exposure to low NaBu concentrations increased expression of proteins involved in angiogenic cell signalling, including p-PKCβ1, p-FAK, p-ERK1/2, p-NFκβ, p-PLCγ1 and p-VEGFR2. In addition, inhibitors of both VEGFR2 and PKCβ1 blocked the angiogenic response. In in vivo assays, low concentrations of NaBu induced neovascularization in sponge implants in mice, evidenced by increased numbers of vessels and haemoglobin content in these implants. The findings in this study indicate that low concentrations of NaBu could be an important compound to stimulate angiogenesis at a site where vasculature is deficient and healing is compromised.

Impaired wound healing states lead to substantial morbidity and cost with treatment resulting in an expenditure of billions of dollars per annum in the U.S. alone. Both chronic wounds and impaired acute wounds are characterized by excessive inflammation, enhanced proteolysis, and reduced matrix deposition. These confounding factors are exacerbated in the elderly, in part, as we report here, related to increased local and systemic tumor necrosis factor-alpha (TNF-α) levels. Moreover, we have used a secretory leukocyte protease inhibitor (SLPI) null mouse model of severely impaired wound healing and excessive inflammation, comparable to age-related delayed human healing, to demonstrate that topical application of anti-TNF-α neutralizing antibodies blunts leukocyte recruitment and NFκB activation, alters the balance between M1 and M2 macrophages, and accelerates wound healing. Following antagonism of TNF-α, matrix synthesis is enhanced, associated with suppression of both inflammatory parameters and NFκB binding activity. Our data suggest that inhibiting TNF-α is a critical event in reversing the severely impaired healing response associated with the absence of SLPI, and may be applicable to prophylaxis and/or treatment of impaired wound healing states in humans.

Metabolomics seeks to measure potentially all the metabolites in a biological sample, and consequently, we need to develop and optimize methods to increase significantly the number of metabolites we can detect. We extended the closed-loop (iterative, automated) optimization system that we had previously developed for one-dimensional GC-TOF-MS (O'Hagan, S.; Dunn, W. B.; Brown, M.; Knowles, J. D.; Kell, D. B. Anal. Chem. 2005, 77, 290−303) to comprehensive two-dimensional (GC×GC) chromatography. The heuristic approach used was a multiobjective version of the efficient global optimization algorithm. In just 300 automated runs, we improved the number of metabolites observable relative to those in 1D GC by some 3-fold. The optimized conditions allowed for the detection of over 4000 raw peaks, of which some 1800 were considered to be real metabolite peaks and not impurities or peaks with a signal/noise ratio of less than 5. A variety of computational methods served to explain the basis for the improvement. This closed-loop optimization strategy is a generic and powerful approach for the optimization of any analytical instrumentation.

Impaired wound healing states in the elderly lead to substantial morbidity and mortality, and a cost to the health services of over 9 billion dollars per annum. In addition to intrinsic ageing processes that per se cause delayed healing, studies have suggested marked differences in wound repair between the sexes. We have previously reported that, castration of male mice results in a striking acceleration of local cutaneous wound healing and dampens the associated inflammatory response. In this study, we report that systemic 5alpha-reductase inhibition, which blocks the conversion of testosterone to its more active metabolite 5alpha-dihydrotestosterone, mimics the effects of castration in a rat model of cutaneous wound healing. The mechanisms underlying the observed effects involve a direct, cell-specific upregulation of pro-inflammatory cytokine expression by macrophages, but not fibroblasts, in response to androgens. Androgens require the transforming growth factor beta signalling intermediate Smad3 to be present in order to influence repair and local pro-inflammatory cytokine levels. That reducing 5alpha-dihydrotestosterone levels through 5alpha-reductase antagonism markedly accelerates healing suggests a specific target for future therapeutic intervention in impaired wound healing states in elderly males.

Age-related impaired wound healing states lead to substantial morbidity and cost, with treatment in the USA resulting in an expenditure of over $9 billion per annum. Dehydroepiandrosterone (DHEA) is a ubiquitous adrenal hormone with immunomodulatory properties whose levels decline significantly with advanced age in humans. Conversion of DHEA locally to downstream steroid hormones leads to estrogenic and/or androgenic effects which may be important in age-related skin homeostasis, and which would avoid systemic adverse effects related to estrogen. We report that systemic DHEA levels are strongly associated with protection against chronic venous ulceration in humans. DHEA accelerated impaired healing in an impaired healing model (mice rendered hypogonadal) associated with increased matrix deposition and dampens the exaggerated inflammatory response. Such effects were mediated by local conversion of DHEA to estrogen, acting through the estrogen receptor, and vitro studies suggest a direct effect on specific pro-inflammatory cytokine production by macrophages via mitogen activated kinase (MAP) and phosphatidylinositol 3 (PI3) kinase pathways. In addition, we show that local injection of DHEA accelerates impaired healing in an ageing mouse colony. We suggest that exogenous application of DHEA accelerates impaired wound repair, results which may be applicable to the prophylaxis and treatment of human impaired wound healing states.

Estrogens play a vital role in the development of sexually dimorphic characteristics essential for reproduction. In recent years, insight has been gained into the role of estrogens in non-reproductive pathophysiological processes, including neoplasia, vascular disease and osteoporosis. Intriguingly, the skin appears to act as an end-organ target for estrogenic action; marked structural and functional skin changes occurring after the menopause can be related to altered hormonal profiles. One of the most important consequences of such hormonal changes is the age-related delay in cutaneous wound healing, leading to substantial morbidity and mortality, and increased costs to health services. Reduced estrogen levels have major downstream effects on cellular and tissue responses to injury; such downstream effects include impaired cytokine signal transduction, unchecked inflammation, and altered protein balance, and have a major impact on the rate of wound healing. Further understanding of the complex interaction between aging cells and the hormonal micro-environment is essential to develop focused therapeutic strategies to improve cutaneous wound healing in hypogonadal individuals, including the elderly.

Humans are exposed to harmful pathogens and a wide range of noxious substances every day. The immune system reacts to, and destroys, these pathogens and harmful substances. The immune system is composed of innate and adaptive immunity, which liaise to protect the host and maintain health. Foods, especially cereals, have been reported to modulate the immune response. Arabinoxylans are nonstarch polysaccharides that have been shown to possess immune-modulatory activities. This review article discusses the fundamentals of the immune system and provides an overview of the immunomodulatory potential of arabinoxylans in conjunction with their structural characteristics and proposed similarities with lipopolysaccharides.

Cutaneous wound healing is a complex process encompassing a number of overlapping events including leukocyte recruitment, matrix deposition, epithelialization, and ultimately resolution of inflammation with the formation of a mature scar. Morbidity associated with age-related delayed wound healing imposes an enormous social and financial burden; unless improved wound care strategies are developed the projected relative and absolute increase in the elderly population will further exacerbate this problem. In recent years insight has been gained into the impact of ageing on cellular and tissue responses, resulting from impaired cytokine signal transduction, unchecked inflammation, an altered balance of protein synthesis and degradation, and subsequent downstream effects on the rate and quality of the wound healing response. Further understanding of the complex interaction between the ageing cell and its microenvironment is essential in order to develop focussed therapeutic strategies to improve healing in the elderly.

C-reactive protein (CRP) is the most acute-phase reactant serum protein of inflammation and a strong predictor of cardiovascular disease. Its expression is associated with atherosclerotic plaque instability and the formation of immature micro-vessels. We have previously shown that CRP upregulates endothelial-derived Notch-3, a key receptor involved in vascular development, remodelling and maturation. In this study, we investigated the links between the bioactive monomeric CRP (mCRP) and Notch-3 signalling in angiogenesis. We used in vitro (cell counting, wound-healing and tubulogenesis assays) and in vivo (chorioallantoic membrane) angiogenic assays and Western blotting to study the angiogenic signalling pathways induced by mCRP and Notch-3 activator chimera protein (Notch-3/Fc). Our results showed an additive effect on angiogenesis of mCRP stimulatory effect combined with Notch-3/Fc promoting bovine aortic endothelial cell (BAEC) proliferation, migration, tube formation in MatrigelTM with up-regulation of phospho-Akt expression. The pharmacological blockade of PI3K/Akt survival pathway by LY294002 fully inhibited in vitro and in vivo angiogenesis induced by mCRP/Notch-3/Fc combination while blocking Notch signalling by gamma-secretase inhibitor (DAPT) partially inhibited mCRP/Notch-3/Fc-induced angiogenesis. Using a BAEC vascular smooth muscle cell co-culture sprouting angiogenesis assay and transmission electron microscopy, we showed that activation of both mCRP and Notch-3 signalling induced the formation of thicker sprouts which were shown later by Western blotting to be associated with an up-regulation of N-cadherin expression and a down-regulation of VE-cadherin expression. Thus, mCRP combined with Notch-3 activator promote angiogenesis through the PI3K/Akt pathway and their therapeutic combination has potential to promote and stabilize vessel formation whilst reducing the risk of haemorrhage from unstable plaques. © 2014 Elsevier Ltd.

Impaired wound healing states lead to substantial morbidity and cost with treatment resulting in an expenditure of billions of dollars per annum in the U.S. alone. Both chronic wounds and impaired acute wounds are characterized by excessive inflammation, enhanced proteolysis, and reduced matrix deposition. These confounding factors are exacerbated in the elderly, in part, as we report here, related to increased local and systemic tumor necrosis factor-alpha (TNF-α) levels. Moreover, we have used a secretory leukocyte protease inhibitor (SLPI) null mouse model of severely impaired wound healing and excessive inflammation, comparable to age-related delayed human healing, to demonstrate that topical application of anti-TNF-α neutralizing antibodies blunts leukocyte recruitment and NFκB activation, alters the balance between M1 and M2 macrophages, and accelerates wound healing. Following antagonism of TNF-α, matrix synthesis is enhanced, associated with suppression of both inflammatory parameters and NFκB binding activity. Our data suggest that inhibiting TNF-α is a critical event in reversing the severely impaired healing response associated with the absence of SLPI, and may be applicable to prophylaxis and/or treatment of impaired wound healing states in humans.

Conditions of impaired wound healing in the elderly are associated with substantial morbidity and mortality and impose a significant financial burden upon the world's health services. The findings of a series of recent studies have served to highlight the contrasting contributions made by sex steroid hormones to the regulation of cutaneous repair processes. Although estrogens accelerate healing, the actions of the "male" sex hormones 5alpha-dihydrotestosterone and testosterone are primarily deleterious. The shift that occurs in the balance between serum estrogen and androgen levels as a normal feature of human aging may therefore have important consequences for fundamental tissue repair processes.

Metabolomics seeks to measure potentially all the metabolites in a biological sample, and consequently, we need to develop and optimize methods to increase significantly the number of metabolites we can detect. We extended the closed-loop (iterative, automated) optimization system that we had previously developed for one-dimensional GC-TOF-MS (O'Hagan, S.; Dunn, W. B.; Brown, M.; Knowles, J. D.; Kell, D. B. Anal. Chem. 2005, 77, 290-303) to comprehensive two-dimensional (GCxGC) chromatography. The heuristic approach used was a multiobjective version of the efficient global optimization algorithm. In just 300 automated runs, we improved the number of metabolites observable relative to those in 1D GC by some 3-fold. The optimized conditions allowed for the detection of over 4000 raw peaks, of which some 1800 were considered to be real metabolite peaks and not impurities or peaks with a signal/noise ratio of less than 5. A variety of computational methods served to explain the basis for the improvement. This closed-loop optimization strategy is a generic and powerful approach for the optimization of any analytical instrumentation.

Venous ulcers are the predominant form of chronic wound in the elderly, accounting for around 70% of all cases. The steroid sex hormone estrogen plays a crucial role in normal human skin maintenance and during cutaneous wound repair following injury. Estrogen can reverse age-related impaired wound healing by dampening the inflammatory response and increasing matrix deposition at the wound site. The molecular actions of estrogen are mediated through two nuclear sex steroid hormone receptors, estrogen receptor alpha (ERalpha) and beta (ERbeta). We have conducted a case-control study to investigate whether dinucleotide repeat polymorphisms in the estrogen receptor genes are associated with venous ulceration in the UK Caucasian population. Genomic fragments containing the ERalpha dinucleotide (TA)(n) repeat polymorphism or the ERbeta dinucleotide (CA)(n) repeat polymorphism were amplified by polymerase chain reaction in subject DNA samples and genotyped according to fragment length by capillary electrophoresis. There was no evidence to suggest that the TA repeat polymorphism of ERalpha was associated with venous ulceration. However, the CA*18 allele of the ERbeta CA repeat polymorphism was significantly associated with venous ulceration (n = 120, OR = 1.8, 95% CI = 1.1-2.8, P = 0.02). When the CA repeats alleles were grouped together into either low (Lor = 18) or high (H18) numbers of CA repeats, the low (L) repeat allele was significantly associated with venous ulceration (OR = 1.5, 95% CI = 1.0-2.2, P = 0.03). Our results show that a specific ERbeta variant is associated with impaired healing in the elderly, predisposing individuals to venous ulceration.

Cutaneous wound healing is a complex process encompassing a number of overlapping events including leukocyte recruitment, matrix deposition, epithelialization, and ultimately resolution of inflammation with the formation of a mature scar. Morbidity associated with age-related delayed wound healing imposes an enormous social and financial burden; unless improved wound care strategies are developed the projected relative and absolute increase in the elderly population will further exacerbate this problem. In recent years insight has been gained into the impact of ageing on cellular and tissue responses, resulting from impaired cytokine signal transduction, unchecked inflammation, an altered balance of protein synthesis and degradation, and subsequent downstream effects on the rate and quality of the wound healing response. Further understanding of the complex interaction between the ageing cell and its microenvironment is essential in order to develop focussed therapeutic strategies to improve healing in the elderly.

Angiotensin I-converting enzyme (ACE) plays a pivotal role in whole body fluid balance and the degradation of bradykinin. A common allelic variant with a 287 base pair insert has been identified on the ACE gene. The homozygous insertion genotype ( II ) corresponds with lower basal serum ACE concentrations compared to the heterozygous ( WI ) and homozygous wild type genotypes ( WW ). Higher circulating levels of ACE may decrease vasodilation; affecting blood flow and sweat loss during exercise. A genotype-independent rise in ACE activity following 20 min of exercise has been reported, but the response to prolonged exercise is unknown. The aim was to examine the influence of ACE genotype on the serum ACE response to exercise in the heat. Healthy Caucasian males ( n =45, 18–45 y) completed 60 min of cycle exercise at (mean ± SD) 62 ± 5% VO 2max in 30.5 ± 0.3°C, with fluid ad libitum . Fluid intake and sweat loss were recorded. Venous blood samples were drawn pre, mid, and postexercise for the determination of serum ACE concentration and ACE genotype. Basal serum ACE concentrations were dependent on ACE genotype ( WW : 215 ± 57 ng.ml -1 ; WI : 158 ± 28 ng.ml -1 ; II : 106 ± 29 ng.ml -1 , P -1 , 166 ± 29 ng.ml -1 and 115 ± 30 ng.ml -1 for WW , WI and II , respectively ( P ACE genotype ( P = 0.321). No differences were found for mean fluid intake ( WW : 613 ± 388 ml; WI : 753 ± 385 ml; II : 862 ± 421 ml, P = 0.31), or sweat loss ( WW : 1013 ± 257 ml; WI : 1048 ± 254 ml; II : 1257 ± 675 ml, P = 0.28). Serum ACE concentration increased independently of ACE genotype within 30 min exercise at 30.5°C. Coupled with the lack of genotype effect on sweat loss and fluid intake, these results suggest ACE genotype plays little role in fluid balance during exercise.

Venous ulcers are characterized by excessive inflammation and raised levels of proinflammatory cytokines. Estrogen has been shown to accelerate the rate of wound healing in elderly subjects by dampening the inflammatory response. The estrogen receptor (ER) proteins, ER-alpha (ERalpha) and ER-beta (ERbeta) mediate the actions of estrogen during wound repair through the activation or repression of target gene transcription. Recent evidence implicates the chromosomal region harboring the ERbeta gene with venous ulceration in a British Caucasian population, highlighting the need to conduct further genetic interrogation. To address this, we conducted a case-control study to investigate whether single nucleotide polymorphisms in the ERbeta gene are associated with venous ulceration in elderly (age >50 years) subjects. We recruited a case group (n = 124, 56 males and 68 females) consisting of patients with an active venous ulcer and a control group consisting of individuals from the general population with no evidence of venous disease or history of venous ulceration (n = 380, 189 males and 191 females). Polymorphisms in close proximity to upstream regulatory regions of the ERbeta gene, including the 0N exon and promoter transcribed in inflammatory cells, were significantly (p < 0.05) associated with venous ulceration. A major susceptibility haplotype carried by 23% (26/112) of cases compared with only 10% (27/276) of controls (odds ratio = 2.8, 95% confidence interval = 1.6-5.0) was significantly (p < 0.01) associated with elevated serum levels of tumor necrosis factor-alpha. In conclusion, common variation in the regulatory regions of the ERbeta gene may pre-dispose to venous ulceration in a British Caucasian population.