Sequential concentrations of placental growth factor and haptoglobin, and their relation to oestrone sulphate and progesterone in pregnant Spanish Purebred mare.

The objectives of this study were to establish reference values for serum concentrations of placental growth factor (PlGF) and haptoglobin (Hp), and to analyze whether the levels of oestrone sulphate (E1S) and progesterone (P4) are physiologically involved in the dynamic modifications of the above parameters in pregnant mares. A total of 30 healthy Spanish Purebred mares ranging in age 9.33 ±â€¯3.31 years were studied during the 11 months of gestation. Serum concentrations of PlGF were detected by EIA, Hp using commercial Phase Haptoglobin assay and E1S and P4 levels through RIA. The serum concentrations of PlGF ranged between 31.70 and 223.60 ng/mL, with a mean value of 57.64 ±â€¯18.05 ng/mL. Serum PlGF levels increased significantly during the 1st and 2nd months, reaching the maximum value in the 3rd month and the minimum value in the 10th month. Hp concentrations increased progressively and significantly from the 5th until the 10th month of gestation (P < 0.05), decreasing in the 11th month of pregnancy. E1S increased significantly from the 3rd until the 7th month, decreasing progressively towards the end of gestation. P4 increased significantly in the 3rd and 4th month and decreased significantly in the 6th and 7th (P < 0.05), with variable oscillations during last months of pregnancy. PlGF and Hp were significantly and negatively correlated (r = -0.27; P < 0.05). In the healthy mare, PlGF and Hp act asynchronously and independent of steroid E1S and P4.

The stress response of Ragusano donkey (Equus asinus) to different semen collection techniques.

The aim of the present study was to characterize the stress response of donkeys to different semen collection techniques, comparing the physiological patterns of hormonal (adrenocorticotropic hormone: ACTH, cortisol) and biochemical variables (creatinine, total protein, urea, aspartate aminotransferase: AST, alanine aminotransferase: ALT), and routine seminal parameters and sexual behaviour. Twenty two healthy Ragusano donkeys were used and were randomly assigned to one of 2 groups based on different semen collection techniques. Group A was designated as the experimental group and included 16 donkeys submitted to semen collection by an artificial vagina (AV) "on the ground"; group B was designated as the control group, and included 6 donkeys submitted to semen collection by AV during the mount. The semen collection was performed in October, once a day for 10 consecutive days. Blood samples were collected in baseline conditions, before the onset of the treatments and within 30 min after, from the jugular vein of each subject. Two-way ANOVA showed a significant effect of semen collection technique and time points in group A for ACTH (p=0.0084), cortisol (p=0.0004) and creatinine (p=0.0131), with lower values after semen collection than before. A significant effect of semen collection technique and time points in group B for ACTH (p<0.0001) and cortisol (p<0.0001) was observed, with higher values after semen collection than before. The comparison between groups A and B values over different time points showed a significant effect after semen collection for ACTH (p<0.0001), cortisol (p<0.0001) and creatinine (p<0.0001), with the highest values in group B. This study provides the physiological evidence that semen collection on the ground in healthy donkeys could be used as an alternative strategy to induce a positive animal approach and economical advantages.

The outcome of the first stages of pregnancy on mares' bloodstream thyroid hormones.

The objective of this study was to compare in detail the total and free iodothyronines' pattern of mares from the first ovulation of the year over an extended period of 12 weeks. A total of 20 mares were used in the study. The mares were classified into two groups: mares mated at the ovulation (n = 10) used as observational group and mares unmated at the ovulation (n = 10) used as control group. Serum total and free triiodothyronine (T3, fT3) and thyroxine (T4, fT4) levels were measured in baseline conditions at the first ovulation of year and once a week until 12 weeks later. For the experimental group, the first week of postovulation mating was considered as the first week of gestation. One-way analysis of variance showed a significant effect of time over 12 weeks for T3 (F = 2.44; P = 0.007) in pregnant mares, with the higher levels at the seventh and 12th weeks (P < 0.05) than baseline values, and for fT3 (F = 2.36; P = 0.009), with the higher levels at the 11th week (P < 0.05) than baseline values. Two-way analysis of variance showed a significant pregnancy effect compared with nonpregnancy stage for T3 (F = 15.82; P = 0.009), with the higher levels at the seventh and 12th weeks (P < 0.05) of pregnancy than that in nonpregnant values. Thus, it appears that, under similar environment, management and nutritional regime, the first trimester of pregnancy plays a dynamic role on the thyroid patterns by their anabolic activity; therefore, significant effects of time points on the T3 and fT3 concentrations probably may contribute to the control of early embryonic growth and development, before the onset of fetal thyroid activity. Considerable additional research, outwith the aim of this study, will be required to elucidate the mechanisms by which gestational age affects the physiological thyroid function in mares and/or fetus ratio in the first pregnancy stage.

Release of ß-endorphin, adrenocorticotropic hormone and cortisol in response to machine milking of dairy cows.

AIM: The present study was undertaken with the objective to obtain insight into the dynamics of the release of ß-endorphin, adrenocorticotrophic hormone (ACTH) and cortisol in response to machine milking in dairy cows. MATERIALS AND METHODS: A total of 10 healthy multiparous lactating Italian Friesian dairy cows were used in the study. Animals were at the 4(th)-5(th) month of pregnancy and were submitted to machine milking 2 times daily. Blood samples were collected in the morning: In baseline conditions, immediately before milking and after milking; and in the early afternoon: In baseline conditions, before milking and after milking, for 2 consecutive days. Endocrine variables were measured in duplicate, using a commercial radioimmunoassay for circulating ß-endorphin and ACTH concentrations and a competitive enzyme-linked immunoassay for cortisol concentration. RESULTS: Data obtained showed a similar biphasic cortisol secretion of lactating dairy cows, with a significant increase of cortisol concentration after morning machine milking, at both the 1(st) and the 2(nd) day (p<0.05), and a decrease after afternoon machine milking at the 2(nd) day (p<0.01). One-way RM ANOVA showed significant effects of the machine milking on the cortisol changes, at both morning (f=22.96; p<0.001) and afternoon (f=15.10; p<0.01) milking, respectively. Two-way RM ANOVA showed a significant interaction between cortisol changes at the 1(st) and the 2(nd) day (f=7.94; p<0.0002), and between the sampling times (f=6.09; p<0.001). Conversely, no significant effects of the machine milking were observed on ß-endorphin and ACTH changes, but only a moderate positive correlation (r=0.94; p<0.06) after milking stimuli. CONCLUSIONS: A wide range of cortisol concentrations reported in this study showed the complex dynamic patterns of the homeostatic mechanisms involved during machine milking in dairy cows, suggesting that ß-endorphin and ACTH were not the main factors that caused the adrenocortical response to milking stimuli.

Effects of weaning on total and free iodothyronines in lambs.

BACKGROUND: Weaning is a crucial period in the management of lambs, resulting in physiological and mental challenges, that may have prolonged effects on lamb's health and welfare. HYPOTHESIS/OBJECTIVES: To evaluate the effect of weaning on total and free triiodothyronine (T3, fT3) and thyroxine (T4, fT4) concentrations in serum of lambs by enzyme immunoassay. Animal and methods: The study was performed on two groups of 17 clinically healthy Comisana cross-bred lambs (7 males and 10 females) with or without weaning at 10 weeks of age. Serum samples were collected at the age of 8 weeks, 24 h and 2 weeks after weaning in the experimental group and at similar times in the non-weaned control group. Enzyme immunoassay was performed. Statistical analysis was done by one-way analysis of variance. RESULTS: Compared to control animals, weaned animals showed significantly decreased T3 and elevated T4 concentrations two weeks after weaning with higher concentrations in both males and females in contrast to 24 h after weaning. Body weight (BW) was significantly restored in both females (11% increase) and males (6%) two weeks after weaning as compared to 24 h after weaning. No gender effects were shown for total and free iodothyronine changes. Significant positive correlations were observed between BW and T4 concentrations in both females (r = 0.692) and males (r = 0.856), fT3 concentrations in males (r = 0.968) and fT4 concentrations in females (r = 0.862). CONCLUSION AND CLINICAL IMPORTANCE: Total iodothyronines could represent an indicator of their different metabolic activity with their magnitude altered two weeks following weaning.

Effect of temperament and prolonged transportation on endocrine and functional variables in young beef bulls.

The purpose of this study was to evaluate the effect of prolonged transportation on adrenocorticotropic hormone (ACTH), cortisol, total and free triiodothyronine (T(3), fT(3)) and thyroxine (T(4), fT(4)) concentrations, and functional variables (heart rate (HR), respiratory rate (RR) and rectal temperature (RT)) in calm and temperamental Limousin young beef bulls. Exit velocity measurement was used to classify bulls' temperament as calm (group I: consisted of eight slowest bulls) and temperamental (group II: consisted of five fastest bulls). Calm subjects showed an increase of ACTH (P<0.05) and T(4) (P<0.01) concentrations after transportation compared with before transportation values. Temperamental subjects showed higher ACTH (P<0.01) concentrations before transportation, and lower T(4) (P<0.05) and fT(4) (P<0.001) concentrations after transportation than calm subjects. Related to functional variables, temperamental young beef bulls showed a decrease of RT (P<0.05) after transportation compared with before values, higher RT (P<0.001) before transportation, and higher HR (P<0.001) and RR (P<0.01) after transportation than calm subjects. Data obtained suggest that longer periods of transportation could minimise the magnitude and duration of the endocrine and functional responses to stress of young beef bulls; such responses probably decrease or disappear during transport, in accordance with animal temperament.

Prolactin regulates luminal bicarbonate secretion in the intestine of the sea bream (Sparus aurata L.).

The pituitary hormone prolactin is a pleiotropic endocrine factor that plays a major role in the regulation of ion balance in fish, with demonstrated actions mainly in the gills and kidney. The role of prolactin in intestinal ion transport remains little studied. In marine fish, which have high drinking rates, epithelial bicarbonate secretion in the intestine produces luminal carbonate aggregates believed to play a key role in water and ion homeostasis. The present study was designed to establish the putative role of prolactin in the regulation of intestinal bicarbonate secretion in a marine fish. Basolateral addition of prolactin to the anterior intestine of sea bream mounted in Ussing chambers caused a rapid (<20 min) decrease of bicarbonate secretion measured by pH-stat. A clear inhibitory dose-response curve was obtained, with a maximal inhibition of 60-65% of basal bicarbonate secretion. The threshold concentration of prolactin for a significant effect on bicarbonate secretion was 10 ng ml(-1), which is comparable with putative plasma levels in seawater fish. The effect of prolactin on apical bicarbonate secretion was independent of the generation route for bicarbonate, as shown in a preparation devoid of basolateral HCO(3)(-)/CO(2) buffer. Specific inhibitors of JAK2 (AG-490, 50 µmol l(-1)), PI3K (LY-294002, 75 µmol l(-1)) or MEK (U-012610, 10 µmol l(-1)) caused a 50-70% reduction in the effect of prolactin on bicarbonate secretion, and demonstrated the involvement of prolactin receptors. In addition to rapid effects, prolactin has actions at the genomic level. Incubation of intestinal explants of anterior intestine of the sea bream in vitro for 3 h demonstrated a specific effect of prolactin on the expression of the Slc4a4A Na(+)-HCO(3)(-) co-transporter, but not on the Slc26a6A or Slc26a3B Cl(-)/HCO(3)(-) exchanger. We propose a new role for prolactin in the regulation of bicarbonate secretion, an essential function for ion/water homeostasis in the intestine of marine fish.

Coumarin-conjugated multiwalled carbon nanotubes for potential biological applications: development and characterization.

This work presents a novel cascade of chemical functionalization of multiwalled carbon nanotubes which allows the conjugation with differently substituted coumarins. Aim of the present work is to synthesize new materials able to rescue cells from the adverse effect of CNT particles since pristine CNTs are practically insoluble and tend to accumulate inside cells, organs and tissues. Moreover, it was reported that single walled CNTs particles show an adverse effect on keratinocytes through an oxidative mechanism, leading to NF-kB activation. The conjugation with coumarins, known superoxide anion scavengers, could switch the cytotoxicity of the new materials. The cascade functionalization of MWCNTs by sequential steps of carboxylation, acylation, amine modification and finally, coumarin conjugation have been performed and the synthesis and the chemical properties of several f-MWCNTs-coumarins have been exploited.

Morphological modification of MWCNT functionalized with HNO3/H2SO4 mixtures.

The acidic oxidation with HNO3/H2SO4 mixtures is widely reported as an effective method to functionalize multi-walled carbon nanotubes (MWCNT). Although effective, a bad control of the oxidation conditions frequently cause serious modifications of carbon nanotube network, limiting further potential applications. Investigations about the effect of functionalization operating conditions on the morphological, chemical and chemical-physical properties of MWCNT can be useful for a proper setting of oxidation reactions of MWCNT according to their specific applications. In this work the effect of HNO3/H2SO4 ratio on the morphological and chemical-physical properties and on the degree of functionalization of MWCNT was investigated. Electron microscopy, thermogravimetric, X-ray diffraction, titration and water dispersion analyses clearly revealed that the increase of the amount of concentrated sulphuric acid in the HNO3/H2SO4 mixture lead to an increase of the amount of functional groups on the MWCNT surface but also to an increase of structural damage in terms of tube cutting and generation of additional defects in the graphitic network of pristine

Influence of endemic goitre areas on thyroid hormones in horses.

The aim of this study was to investigate thyroid hormone levels in horses stabled in two different locations on the island of Sicily. The study was carried out on a total of 72 clinically healthy Sanfratellano horses ranging in age from 5 to 9 years and weighing 585 ± 40 kg. The results showed higher thyroxine values (P < 0.02) in horses stabled in an endemic goitre area (group II) than those observed in horses in a non-endemic area (group I). Unexpectedly, the T(4)/T(3) and the fT(4)/fT(3) rations were both lower in group I than in group II. The percentages of fT(4) to T(4) and of fT(3) to T(3) were both higher in group I than the percentages for group II. On the basis of gender, comparison between the two groups showed higher T(4) (P < 0.01) and fT(4) levels (P < 0.001) in males, and lower fT(3) (P < 0.001) and fT(4) levels (P < 0.005) in females stabled in the goitre endemic area. On the basis of age, younger horses (<7 years old) showed the highest thyroid hormone levels in both groups. Results suggest a physiological adaptive response of the equine species to an endemic goitre environment. The possibility that hypothyroidism is present in these horses is thus excluded and is supported not only by the lack of clinical signs, but also by the rarity of cases previously reported.

Effects of fence height on total and free iodothyronine changes in horses after experimental show jumping sessions.

REASONS FOR PERFORMING STUDY: Involvement of thyroid function on performance warrants further investigation as limited data exists on the effects of showjumping on the dynamics of total and free iodothyronines. OBJECTIVES: To investigate the response of circulating total and free iodothyronines in horses to experimental showjumping sessions and compare with the effects normally induced by competition and determine if fence height has any effect. MATERIALS AND METHODS: Using a randomised crossover study design 6 trained horses were studied during experimental showjumping sessions over 10 fences of different height: 1.00 m (Session 1), 1.10 m (Session 2), 1.20 m (Session 3). Hormone levels were recorded before, after warm-up, 5 and 30 min post exercise. T(3), T(4), fT(3), fT(4) concentrations were analysed by ELISA/competition using streptavidin technology. RM-ANOVA was applied to test for any differences in basal and warm-up values of different sessions. Two way RM-ANOVA was applied to test for any effects of interaction between fence height and time. The differences between individual means over time were assessed using a post hoc multiple comparison test (Bonferroni). RESULTS: Basal T(4) changes over the sessions (P < 0.05) were recorded. After warm-up, T(4) concentration results were lower than basal in Session 1 (P < 0.05). Higher than basal values were recorded 30 min post exercise for T(3) (P < 0.001), T(4) and fT(4) (P < 0.01) in Session 2 and for T(4) (P < 0.05) and fT(4) (P < 0.01) in Session 3. The interaction fence height/time results were significant on T(3) (P < 0.03) and fT(4) (P < 0.03); sampling time on T(3) (P < 0.0007), T(4) (P < 0.001) and fT(4) (P < 0.002) post exercise changes. CONCLUSION: Showjumping over the highest fences induced a release of T(3) from skeletal muscle, probably due to 5'-desiodase activity and increase of fT(4), due to thyroid stimulation and/or changes in capacity to bind iodothyronines.

Cortisol and haematochemical variables of horses during a two day trekking event: effects of preliminary transport.

REASONS FOR PERFORMING STUDY: Trekking is a noncompetitive sport, involving maximal skeletal muscle effort. Exercise and transport may involve significant energy expenditure and give rise to substantial stress. Few studies have examined the combined effect of exercise and additional preliminary transport on adrenocortical and haematochemical responses in horses during trekking. OBJECTIVES: To ascertain whether exercise and additional preliminary transport before trekking would affect the circulating cortisol levels and haematochemical variables of horses during a 2 day trekking event. MATERIALS AND METHODS: Twenty-nine healthy horses were used. Twenty-four horses were transported over distances of 70 km the day before trekking and 5 horses were stabled at the starting place. Blood samples were taken from horses at 16.00 h the day before trekking; and at 08.30 h and 17.30 h before and after the first day of trekking; at 08.30 h and at 13.30 h before and after the second day of trekking. Serum cortisol and haematochemical variables were determined in duplicate by using commercial test kits. One-way analysis of variance for repeated measures (RM-ANOVA) was applied to determine whether trekking and transport had any effects. RESULTS: Trekking significantly (P < 0.01) affected total protein, albumin, urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT), PCV and cortisol changes in transported horses and only urea and PCV (P < 0.01) changes in untransported horses. Untransported horses showed lower basal total protein (P < 0.05) and albumin (P < 0.01) concentrations, higher urea concentrations (P < 0.001) at the second day and lower cortisol levels after the first and the second (P < 0.05) day of trekking than transported horses. CONCLUSION: These data show that the preliminary transport stress induced additional significant changes of cortisol and haematochemical patterns in horses after trekking.

Effects of competitive and noncompetitive showjumping on total and free iodothyronines, ß-endorphin, ACTH and cortisol levels of horses.

REASONS FOR PERFORMING STUDY: Limited knowledge exists about the differentiated effects of competitive and noncompetitive showjumping on thyroid function and relationships with hypothalamic-hypophysis-corticoadrenal hormones. OBJECTIVES: To obtain preliminary data about differentiated effects of competitive and noncompetitive showjumping on total and free iodothyronines, ß-endorphin, ACTH and cortisol of horses. MATERIAL AND METHODS: Five trained healthy jumper horses were studied during competitive and noncompetitive showjumping, performed in the same circuit design over 10 fences of 1.10 m. Hormone levels before, 5 and 30 min post exercise were recorded. Serum iodothyronines and cortisol concentrations were measured in duplicate utilising EIA kits. Serum ACTH and plasma ß-endorphin concentrations were analysed in duplicate utilising RIA kits. Two-way RM ANOVA was applied to test for effects of interaction between different type of session and time. Significant differences between post exercise and basal values were established using Bonferroni's multiple comparison test. A linear correlation analysis (Pearson's method) was performed to analyse the relationships between total and free iodothyronines and between iodothyronines and ß-endorphin, ACTH and cortisol. RESULTS: In sampling times adopted no statistical different effects of type of session were recorded on hormone variables. Sampling time affected ACTH (F = 4.25; P < 0.02) and T(4) (F = 4.43; P < 0.02) post exercise changes. During the noncompetitive session, significant correlations existed between T(4) and ß-endorphin (r = -0.56), ACTH (r = -0.65), between ß-endorphin and ACTH (r = 0.52) and between T(3) and fT(3) (r = 0.72); during competition between ß-endorphin and T(3) (r = -0.67), fT(3) (r = -0.59). CONCLUSIONS: These preliminary results could demonstrate correlations between thyroid hormones and ß-endorphin response to showjumping, although no definitive conclusion can be produced concerning the relationships between HPA and thyroid function during exercise.

Plasma serotonin levels in Italian Fresian dairy cows.

The aim of this work was to investigate the metabolism of plasma serotonin or 5-hydroxytryptamine (5-HT), an important neurotransmitter, in Fresian dairy cows, a breed of zootechnical interest, using high-performance liquid chromatography with electrochemical detection. The subjects under study were at the stage of early lactation (n = 10; mean body weight 375 +/- 50 kg; average age of 3 years; body condition score 2.5), bred in a farm at an altitude of 150 m a.s.l. To evaluate animal welfare on this farm, which is closely connected to an animal's physiological status, tryptophan and cortisol levels (measured by enzyme-linked immunosorbent assay), together with levels of certain blood components [total proteins (TP), albumin, creatinine, glucose (Glu), triglycerides, phospholipids, total cholesterol, and aspartate transaminase, measured by spectrophotometry] were analyzed. The results obtained are discussed in comparison with reference values, taking into account the environmental living conditions. Measured plasma serotonin concentrations, which were lower than values reported for Brown Swiss dairy cows of a comparable age and diet, appeared to be affected by breed, temperature, blood sampling season, and altitude. Additional differences between the levels of plasma tryptophan, the amino acid precursor of serotonin, of the two breeds were comparable. Negative correlations between plasma tryptophan and plasma cortisol levels (r = -0.83, P < 0.005), plasma serotonin and plasma TP levels (r = -0.72, P < 0.05), or Glu levels (r = -0.77, P < 0.05) highlight the existence of a stress condition, which is connected to an energetic deficit related to lactation.

Physiological variables of horses after road transport.

In order to investigate the effects of short road transport stress on total and free iodothyronines, body weight (BW), rectal temperature and heart rate (HR) changes, 126 healthy stallions were studied in basal conditions, before and after transport. A total of 60 Thoroughbred and 66 crossbred stallions aged 4 to 15 years with previous travelling experience were transported by road in a commercial trailer for a period of about 3 to 4 h (distance under 300 km). Blood samples and functional variables were collected in each horse box, one week before loading and transport in basal conditions (control samples), one week later immediately before loading (pre-samples) and again after transport and unloading (about 3 to 4 h) in each new horse box, within 30 min of their arrival at the breeding stations (post-samples). Compared to the before-transport values, increases in circulating T3, T4 and fT4 levels (P < 0.01) were observed after transport, irrespective of breed, but not for fT3 levels. Lower T4 and fT4 levels were observed in basal II (at 1100 h) (P < 0.01) than in basal I (at 0800 h) conditions and before transport. Thoroughbreds showed higher fT3 (P < 0.05) and fT4 (P < 0.01) levels after transport than crossbred stallions. No significant differences were observed for T3 and T4. Compared to the before-transport values, significant increases in rectal temperature (P < 0.01) and HR (P < 0.05) were observed after transport. No differences were observed between basal I, II and before values for functional variables. Significant correlations between T3 and rectal temperature, BW and HR were found. The results indicate that short road transport induces a preferential release of T3, T4 and fT4 hormones from the thyroid gland in relation to different breed, and an increase in rectal temperature and HR. No significant changes in BW were observed. No differences were observed in relation to different ages. The data obtained suggest that the stallion's thyroid hormones and functional variables may play an important role in assessing the effects of transport stress and a horse's coping strategy.

Effects of competition experience and transportation on the adrenocortical and thyroid responses of horses.

To evaluate whether the amount of experience of sport horses and the stress of transport affected their adrenocortical and thyroid responses, the plasma concentrations of total cortisol and total and free iodothyronine of 63 horses were studied before and after show jumping competitions. There were 14 trained inexperienced jumpers (group 1), 20 trained experienced jumpers (group 2), 10 trained inexperienced jumpers that had been transported just before the competition (group 3) and 19 trained experienced jumpers that had been transported just before the competition (group 4). The concentrations were measured under basal conditions and five and 30 minutes after the competition. There were significant increases relative to the basal values in the total cortisol concentrations of all four groups of horses at five and 30 minutes (P<0.001), but there were no significant differences between the groups. In contrast, there were no significant changes in the concentrations of triiodothyronine, thyroxine and free thyroxine after the competition and there were no significant differences between the groups. However, the horses in group 2 had significantly lower basal concentrations of free triiodothyronine than the horses in groups 1, 3 and 4 and the difference was maintained at five and 30 minutes after the competition.

Differential effect of growth factors on hyaluronan synthase gene expression in fibroblasts exposed to oxidative stress.

The aim of this study was to evaluate how growth factors (PDGF-BB, EGF, and TGF-1beta) modulate hyaluronan synthase (HAS) activities in normal or stressed cultured human skin fibroblasts. The effects of concomitant treatment with cytokines and FeSO4 plus ascorbate on HAS mRNA expression, protein synthesis, and hyaluronic acid (HA) concentrations were also studied. Treatment of fibroblasts with growth factors up-regulated HAS gene expression and increased HAS enzymes and HA production. PDGF-BB induced HAS mRNA expression, protein synthesis, and HA production more efficiently than EGF and TGF-1beta. EGF was less effective than TGF-1beta. In addition, TGF-1beta reduced the expression and synthesis of HAS3, while PDGF-BB and EGF had the opposite effect. Concomitant treatment with growth factors and the oxidant was able to further increase HAS mRNA expression, once again with the exception of HAS3 with TGF-1beta. HAS protein synthesis was reduced, while HA levels were unaffected in comparison to those obtained from exposure to FeSO4 plus ascorbate alone. In conclusion, although growth factors plus the oxidant synergistically induced HAS mRNA expression in part, enzyme production was not correlated with this increase. Moreover, the increase in HAS mRNA levels was not translated into a consequent rise in HA concentration.

Chondroitin sulphate: antioxidant properties and beneficial effects.

Most biological molecules exhibit more than one function. In particular, many molecules have the ability to directly/indirectly scavenge free radicals and thus act in living organisms as antioxidant. During oxidative stress, the increase of these molecules levels seems to be a biological response that in synergism with the other antioxidant defence systems may protect cells from oxidation. Among these structures, chondroitin sulphate is a biomolecule which has increasingly focused the interest of many research groups due to its antioxidant activity. This review briefly summarises the action of chondroitin sulphate in reducing molecular damage caused by free radicals and associated oxygen reactants.