Increased plasma plant sterol levels in heterozygotes with sitosterolemia and xanthomatosis

Plasma sterol levels in a family of sitosterolemia and xanthomatosis were determined by a high performance liquid chromatography. Three affected siblings manifested marked xanthomatosis including subcutaneous soft tissues and generalized atherosclerosis. Two other siblings as well as children of the patients did not show such clinical symptoms and signs. Plasma levels of cholesterol, sitosterol, campesterol, and cholestanol in three affected subjects were 190 +/- 18.5, 25.9 +/- 11.6, 16.1 +/- 7.8, 1.84 +/- 0.92 mg/dl (mean +/- SD), respectively. Four daughters of the affected subjects, who should be considered as obligatory heterozygotes, showed moderately increased levels of these sterols (195 +/- 41.7, 1.33 +/- 0.44, 1.56 +/- 0.69, 0.80 +/- 0.28 mg/dl), which were significantly higher than those of normal subjects. Treatment with cholestyramine had little effect on the increased plasma plant sterol levels, but markedly decreased plasma cholestanol concentrations in two affected siblings. This report presents the clinical features of the patients with sitosterolemia and xanthomatosis and also demonstrates that heterozygotes with this disorder have increased plasma levels of plant sterols as well as cholestanol, and suggests that this rare disease might be inherited as an autosomal co-dominant trait in certain cases. The data also indicate that cholestyramine administration was not effective in this family for treatment of sitosterolemia.     

Increased plasma corticosterone levels in bovine growth hormone (bGH) transgenic mice: Effects of ACTH,GH and IGF-I onin vitro adrenal corticosterone production

Previous work from our laboratory provided evidence for increased plasma corticosterone levels in mice transgenic for human and bovine growth hormone (GH). Corticosterone was elevated in both sexes, under both basal and ether-induced stress conditions. The objectives of the present study were to investigate thein vitro adrenal sensitivity to ACTH, GH and/or IGF-I in normal and bGH transgenic mice, to examine plasma corticosterone levels at different times of the day, and to determine plasma levels of ACTH in these animals. For the measurement of plasma corticosterone and ACTH levels, transgenic and normal siblings were housed 2 per cage and decapitated simultaneously within 20 seconds of the first disturbance of the cage. The corticosterone production byin vitro adrenal incubations did not differ between adrenals from normal and transgenic mice at the basal level or in the presence of different doses of ACTH. Growth hormone or IGF-I did not have any effect on corticosterone productionin vitro when given alone, and did not modify the effects of ACTH on the accumulation of corticosterone in the media. Plasma corticosterone concentrations were higher in transgenic than in normal animals in both morning and evening. Plasma concentrations of ACTH in animals killed in the morning were sharply increased in transgenic males as compared with their normal siblings. The results indicate that increased circulating levels of corticosterone in transgenic mice are not due to a potentiation of ACTH actions by GH or IGF-I, but rather to a chronic increase in plasma ACTH levels. The increase in ACTH is presumably a reflection of GH actions in the hypothalamic-pituitary system.     

Influence of plasma lipid changes in response to 17β-oestradiol stimulation on plasma growth hormone, somatostatin, and thyroid hormone levels in immature rainbow trout

Plasma total lipids were significantly higher in 17β-oestradiol(E₂)-treated immature rainbow trout Oncorhynchus mykiss at week 4 after implantation, due to increases in polar and neutral lipids. The lipid classes responding were phosphatidylcholine, phosphatidylinositol, phosphatidylethanolamine, sterols and sterol esters, in a proportion that approximately reflected the increase in plasma vitellogenin (VtG) levels as measured by a non-competitive enzyme-linked immunosorbent assay (ELISA). Plasma non-esterified fatty acids and triacylglycerol were not affected by E₂ treatment. Plasma growth hormone GH levels were increased, and plasma somatostatin-14 (SRIF) levels decreased in E₂-treated fish, responses which could be secondary to elevated plasma lipid (VtG) content, although a direct E₂ action on somatotroph function is possible. Plasma T₄ concentrations were not affected by E₂ treatment, but plasma T₃ concentrations were significantly lower than in controls 1 week after implantation when plasma E₂ concentrations were the highest; this is in support of the hypothesis that E₂ has a suppressive action on T₃ production.     

Associations between the Duration of Dialysis,Endotoxemia, Monocyte Chemoattractant Protein-1, and the Effects of a Short-Dwell Exchange in Patients Requiring Continuous Ambulatory Peritoneal Dialysis

Background

Endotoxemia is exaggerated and contributes to systemic inflammation and atherosclerosis in patients requiring continuous ambulatory peritoneal dialysis (CAPD). The risk of mortality is substantially increased in patients requiring CAPD for >2 years. However, little is known about the effects of long-term CAPD on circulating endotoxin and cytokine levels. Therefore, the present study evaluated the associations between plasma endotoxin levels, cytokine levels, and clinical parameters with the effects of a short-dwell exchange on endotoxemia and cytokine levels in patients on long-term CAPD.

Methods

A total of 26 patients were enrolled and divided into two groups (short-term or long-term CAPD) according to the 2-year duration of CAPD. Plasma endotoxin and cytokine levels were measured before and after a short-dwell exchange (4-h dwell) during a peritoneal equilibration test (a standardized method to evaluate the solute transport function of peritoneal membrane). These data were analyzed to determine the relationship of circulating endotoxemia, cytokines and clinical characteristics between the two groups.

Results

Plasma endotoxin and monocyte chemotactic protein-1 (MCP-1) levels were significantly elevated in the long-term group. PD duration was significantly correlated with plasma endotoxin (r = 0.479, P = 0.016) and MCP-1 (r = 0.486, P = 0.012). PD duration was also independently associated with plasma MCP-1 levels in multivariate regression. Plasma MCP-1 levels tended to decrease (13.3% reduction, P = 0.077) though endotoxin levels did not decrease in the long-term PD group after the 4-h short-dwell exchange.

Conclusion

Long-term PD may result in exaggerated endotoxemia and elevated plasma MCP-1 levels. The duration of PD was significantly correlated with circulating endotoxin and MCP-1 levels, and was an independent predictor of plasma MCP-1 levels. Short-dwell exchange seemed to have favorable effects on circulating MCP-1 levels in patients on long-term PD.     

Effects of interleukin-2 (IL-2) on human plasma lipid,lipoprotein, and C-reactive protein

Six patients with confirmed malignant disease received four consecutive weekly cycles of human recombinant interleukin-2 (IL-2) 4 days/week, continuous iv. infusion, 3 × 10⁶ U/m²/day. Plasma cholesterol decreased a mean of 7% within 24 hours after IL-2 infusion and decreased by 33% within 4 days. Plasma cholesterol was significantly lower than baseline concentration by day 21 (–21%), and day 25 (–41%) was significantly lower than day 21. Decreased plasma cholesterol was the result of decreased HDL and LDL cholesterol concentrations. Plasma triglyceride demonstrated a mean increase of 46% after 4 days of therapy and remained greater than baseline concentrations at all time points analyzed. Apolipoprotein AI and AII decreased concomitantly with HDL-cholesterol concentrations, whereas apolipoprotein B after an initial mean decrease of 17% during the first cycle was not significantly different from baseline during the fourth cycle. Apolipoprotein E and Lp(a) were not significantly affected by IL-2 treatment. Plasma C-reactive protein (CRP) increased by 79% within 24 hours of therapy, increased by 254% on day 4, then decreased to baseline concentrations by day 21 after 3 days off of IL-2. Day 25 CRP was elevated compared to both baseline and day 21 concentrations. IL-2 induced plasma lipoprotein changes may be due in part to the induction of interferon gamma.     

Clopidogrel, a P2Y12 receptor antagonist, potentiates the inflammatory response in a rat model of peptidoglycan polysaccharide-induced arthritis

The P2Y12 receptor plays a crucial role in the regulation of platelet activation by several agonists, which is irreversibly antagonized by the active metabolite of clopidogrel, a widely used anti-thrombotic drug. In this study, we investigated whether reduction of platelet reactivity leads to reduced inflammatory responses using a rat model of erosive arthritis. We evaluated the effect of clopidogrel on inflammation in Lewis rats in a peptidoglycan polysaccharide (PG-PS)-induced arthritis model with four groups of rats: 1) untreated, 2) clopidogrel-treated, 3) PG-PS-induced, and 4) PG-PS-induced and clopidogrel-treated. There were significant differences between the PG-PS+clopidogrel group when compared to the PG-PS group including: increased joint diameter and clinical manifestations of inflammation, elevated plasma levels of pro-inflammatory cytokines (IL-1 beta, interferon (IFN) gamma, and IL-6), an elevated neutrophil blood count and an increased circulating platelet count. Plasma levels of IL-10 were significantly lower in the PG-PS+clopidogrel group compared to the PG-PS group. Plasma levels of platelet factor 4 (PF4) were elevated in both the PG-PS and the PG-PS+clopidogrel groups, however PF4 levels showed no difference upon clopidogrel treatment, suggesting that the pro- inflammatory effect of clopidogrel may be due to its action on cells other than platelets. Histology indicated an increase in leukocyte infiltration at the inflammatory area of the joint, increased pannus formation, blood vessel proliferation, subsynovial fibrosis and cartilage erosion upon treatment with clopidogrel in PG-PS-induced arthritis animals. In summary, animals treated with clopidogrel showed a pro-inflammatory effect in the PG-PS-induced arthritis animal model, which might not be mediated by platelets. Elucidation of the mechanism of clopidogrel-induced cell responses is important to understand the role of the P2Y12 receptor in inflammation.     

Cortisol and thyroid hormone responses to acid stress in the brown trout, Salmo trutta L.

Individual cannulated brown trout monitored during exposure to acidic water showed increased plasma cortisol after 3 h at pH 4.0 with low (0.05 mm) or high (2.8 mm) calcium (Ca) content, and after 2 days in acidic water with a high Ca content. Most fish did not survive for 2 days in acidic water with a low Ca content. Non-cannulated fish showed a similar increase in mean plasma cortisol after 2 days in high-Ca acidic water (pH 4.0–4.6), but not in acidic water of a low Ca content. After 7 days of exposure to acidic water, plasma cortisol appeared to recover when there was a high Ca content but increased 20-fold when Ca content was low. In cannulated fish severe acid stress resulted in a marked and rapid thyroid response. Plasma thyroxine (T₄) was elevated after 3 h exposure to acidic water of both low and high Ca content and remained elevated for 2 days of acid exposure with high Ca. In non-cannulated fish an increase in mean T₄ was apparent only after 7 days in low-Ca acidic water. Plasma triiodothyronine (T₃) levels were not significantly altered by any of the acid regimes. Plasma glucose of cannulated fish was elevated within 3 h of acid-exposure and remained elevated after 2 days in high-Ca acidic water.     

Chromium and yogurt effects on hepatic lipid and plasma glucose and insulin of obese mice

Dietary chromium (Cr) supplements in casein or yogurt-based diets were fed to genetically obese C57BL/6J-OB (ob/ob) mice to investigate the effects of Cr and yogurt on total hepatic lipid, plasma glucose, insulin, and cholesterol levels. Diet groups were casein control (C), yogurt control (Y), yogurt plus CrCl₃ (Y + Cr) (1.83 ppm Cr), and casein plus CrCl₃ (C + Cr) (1.85 ppm Cr). Food and water were availablead libitum. No significant differences were observed in final body weight. In obese mice, total hepatic lipid was significantly greater in the C than in the C + Cr group and in the Y than in the Y + Cr group. Plasma immunoreactive insulin levels tended to be lower in animals fed C + Cr and Y + Cr diets. Plasma insulin was significantly correlated with hepatic lipid and with plasma cholesterol. By analysis of variance, bone Cr was elevated by Cr supplementation. In the obese mouse, a model for insulin resistance, Cr supplementation apparently affects both hepatic lipid concentration and bone chromium.     

Effect of ergotamine on plasma metabolite and insulin-like growth factor-1 concentrations in cows

Bovine plasma was assayed to determine if ergotamine affected plasma metabolite and insulin-like growth factor-1 (IGF-1) concentrations. In Experiment 1, four cows received a single bolus intravenous injection of ergotamine tartrate (19 microg/kg body wt.) or saline vehicle in a crossover design 2 days after prostaglandin-induced luteolysis. Treatmentxtime affected plasma glucose, triglyceride, total cholesterol and IGF-1 concentrations. Glucose and cholesterol were increased after ergotamine. Triglycerides were elevated within 1 h after ergotamine, but were decreased 3 h after ergotamine treatment. Plasma IGF-1 decreased in response to ergotamine. Blood constituents were unchanged after treatment with saline. In Experiment 2, six cows received a single bolus intravenous injection of ergotamine (20 microg/kg body wt.) or saline vehicle in a crossover design 10 days after receiving norgestomet (6 mg) via subcutaneous ear implant. Treatmentxtime affected glucose, triglycerides, total cholesterol and IGF-1 concentrations. Glucose and cholesterol were increased after ergotamine. Triglycerides were elevated 1 h after ergotamine and decreased 3-7 h after ergotamine. Plasma IGF-1 decreased after ergotamine treatment. Blood constituents were unresponsive to the saline vehicle. Results indicated ergotamine altered plasma metabolite and IGF-1 concentrations in cows.     

A new peroxisomal disorder with enlarged peroxisomes and a specific deficiency of Acyl-CoA oxidase (pseudo–Neonatal adrenoleukodystrophy)

In the present paper two siblings are presented with clinical manifestations very similar to those of patients affected by neonatal adrenoleukodystrophy. In contrast to neonatal adrenoleukodystrophy patients, hepatic peroxisomes in these siblings were enlarged in size and not decreased in number. Accumulation of very-long-chain fatty acids (VLCFA) was associated with an isolated deficiency of the fatty acyl-CoA oxidase, the enzyme that catalyzes the first step of the peroxisomal beta-oxidation. Plasma levels of di- and trihydroxy-coprostanoic acid, phytanic acid, and pipecolic acid were normal; furthermore, acyl-CoA:dihydroxyacetone phosphate acyltransferase activity in cultured fibroblasts was also found to be normal. The clinical, biochemical, and cytochemical features found in these two siblings are compared with those seen in two other disorders characterized by the absence of a decreased number of hepatic peroxisomes and the presence of VLCFA: (1) pseudo-Zellweger syndrome (deficiency of peroxisomal thiolase activity) and (2) X-linked childhood adrenoleukodystrophy (deficiency of activation of lignoceric acid). Review of the different biochemical defects possible in very-long-chain fatty-acid oxidation reveals different clinical pictures of varying severity, depending on the level at which the biochemical defect occurs.     

Plasma gonadotrophins, prolactin and corticosterone concentrations in male mice exposed to high altitude

Groups of sexually-naive male NFR/N mice were maintained at sea level or exposed to simulated altitudes of 18 000 ft (5486 m) or 22 000 ft (6705 m) for 1, 3, 7, 14 or 28 days. Plasma LH concentrations were slightly but not significantly depressed after 1 day of hypoxia. Plasma FSH values were reduced (P < 0.05) after 1, 7, 14 and 28 days of exposure to 22 000 ft when compared to the values in the other groups. Prolactin concentrations fluctuated considerably, but were not uniformly affected by high altitude exposure. Exposure to 18 000 ft resulted in an elevation of plasma corticosterone concentration (P < 0.05) for 3 days, which was followed by a decline to control group values, whereas at 22 000 ft corticosterone levels remained elevated. These findings indicate that plasma LH values are transiently reduced during the initial 24 h of exposure to high altitude and that plasma FSH concentrations are depressed in a sustained manner during severe hypoxia.     

The influence of diet and carnitine supplementation on plasma carnitine, cholesterol and triglyceride in WHHL (Watanabe-heritable hyperlipidemic), Netherland dwarf and New Zealand rabbits (Oryctolagus cuniculus)

1. Plasma carnitine levels in the spontaneously (endogenously) hyperlipidemic Watanabe (WHHL) rabbit are approximately 2-fold higher (P less than 0.001) than in normal rabbits of the New Zealand (NZ) or Netherland Dwarf (NDw) breeds. 2. Plasma carnitine levels in WHHL (44 +/- 3 nmol/ml) can be approximated in NZ and NDw which are rendered exogenously hyperlipidemic by supplementation of the stock chow diet with cholesterol and peanut oil. 3. The induction of endogenous hyperlipidemia in NZ by feeding a sucrose casein rich diet results in a biphasic response of plasma carnitine (elevation followed by normalization). 4. Plasma carnitine in WHHL is readily elevated by supplemental L-carnitine and the elevation is associated with a reduction in plasma triglyceride which shows differences in individual response time; plasma cholesterol is unaffected by supplemental L-carnitine.     

Lipid dynamics in goldfish (Carassius auratus) during a period of gonadal recrudescence: Effects of beta-sitosterol and 17beta-estradiol exposure

The potential for contaminants to alter lipid or cholesterol dynamics in fish is rarely investigated and may include critical physiological endpoints that are impacted by exposure to endocrine-active substances. The current study investigated plasma and tissue lipid dynamics over a period of recrudescence in goldfish, while also examining the potential for beta-sitosterol (beta-sit), a phytosterol and 17beta-estradiol (E(2)), an endogenous estrogen, to alter lipid homeostasis. Goldfish were exposed to 0 microg/g (no chemical; control), 200 microg/g beta-sit (72.3% sitosterol mixture) or 10 microg/g 17beta-estradiol (E2) via Silastic implants for a period of five months. Plasma lipids peaked in control fish coincident with maximum liver size, while gonadal cholesterol concentration was highest concomitant with maximum gonad size. Plasma lipid concentrations were highly affected by E2 but not beta-sit exposure; E2 elevated total cholesterol (p<0.001) and triglyceride (TG; p<0.001) and decreased high-density lipoprotein (HDL) concentration (p<0.001) in male fish. Tissue cholesterol concentrations were minimally affected by beta-sit exposure, while hepatic cholesterol concentrations were increased in E2 exposed females (p=0.041), indicating elevated liver lipogenesis in response to E2, but not beta-sit, exposure. The present study demonstrates differential effects by beta-sit and E2 on plasma lipoprotein profile and TG concentration and indicates estrogen-specific effects on hepatic lipid metabolism during gonadal development.     

Freeze-fracture electron microscopic studies of age-related plasma membrane changes in Sporothrix schenckii

Characteristics of the plasma membrane of Sporothrix scheckii cells as revealed by freeze-fracture techniques have been classified into eight types (Y1, Y2a, Y2b, Y3a, Y3b, Y4a, Y4b, and Y5) in yeastlike cells grown under the following two conditions: brain heart infusion agar medium at 27 degrees C, and brain heart infusion agar medium at 37 degrees C. Type Y1 cells are yeastlike cells having smooth plasma membranes without any invagination. Typical characteristics of the other types are as follows: type Y2a, smooth plasma membranes with few trenchlike invaginations; type Y2b, wavy plasma membranes with few oval or irregularly formed invaginations; type Y3a, plasma membranes with many randomly distributed trenchlike invaginations; type Y3b, plasma membranes with many cocoonlike or irregularly formed invaginations; type Y4a, plasma membranes with longer trenchlike invaginations; type Y4b, plasma membranes with irregularly formed, enlarged invaginations; and type Y5, smooth or wavy plasma membranes with aggregations of intramembranous particles and with many vacuoles between cell walls and plasma membranes or in the cytoplasm in some cells. By counting the proportion of each type of yeastlike cell under the two conditions and with different cultivation periods, it appears that plasma membrane types change as aging progresses in the following order: type Y1, Y2a, Y3a, Y4a, and Y5 in conidia and type Y1, Y2b, Y3b, Y4b, and Y5 in yeastlike vegetative cells. These observations provide us with an important advantage when studying the effects of antifungal agents on the plasma membrane of Sporothrix scheckii, as it is important to know the natural course of changes in membrane structure during aging.     

Hyperlipidemia and reproductive failure in captive-reared alligators: vitamin E, vitamin A, plasma lipids, fatty acids, and steroid hormones

Blood samples were collected from 26 captive-reared alligators (25 females; one male) and 12 (seven females and five males) wild "nuisance" alligators collected by wildlife personnel in south Louisiana in May 1995. The captive alligators, hatched from artificially incubated eggs in 1972-1973, had received vitamin E supplements during the 3 weeks before the blood sample was collected. Each sample was analyzed for vitamin E (alpha-tocopherol), vitamin A (retinol), total lipid, triacylglycerol, phospholipid, cholesterol, cholesteryl ester, free fatty acids, steroid hormones and a standard clinical blood panel. The fatty acid composition of the plasma lipid fraction was also analyzed. Results indicated that 18 of the captive females and three of the seven wild females were undergoing vitellogenesis, i.e. had elevated plasma estradiol and elevated plasma calcium. Vitellogenic females had higher vitamin E than non-vitellogenic females (77.4 microg/ml vs. 28.6 microg/ml in captive females; 24.0 microg/ml vs. 21 microg/ml in wild females). Plasma retinol was similar in all groups, ranging from 0.5 to 1.4 microg/ml and close to values reported in birds. All lipid fractions, with the exception of cholesteryl ester, were higher in captive alligators than in wild alligators. There were also significant differences in the fatty acid composition of wild and captive alligators. Plasma eicosapentaenoic and docasahexaenoic acid were higher in wild than in captive alligators, whereas linoleic was higher in captive than in wild.     

Increased serum heat-shock protein 70 levels reflect systemic inflammation, oxidative stress and hepatocellular injury in preeclampsia

It has been previously reported that serum levels of 70-kDa heat-shock protein (Hsp70) are elevated in preeclampsia. The aim of the present study was to examine whether increased serum Hsp70 levels are related to clinical characteristics and standard laboratory parameters of preeclamptic patients, as well as to markers of inflammation (C-reactive protein), endothelial activation (von Willebrand factor antigen) or endothelial injury (fibronectin), trophoblast debris (cell-free fetal DNA) and oxidative stress (malondialdehyde). Sixty-seven preeclamptic patients and 70 normotensive, healthy pregnant women were involved in this case-control study. Serum Hsp70 levels were measured with enzyme-linked immunosorbent assay (ELISA). Standard laboratory parameters (clinical chemistry) and C-reactive protein (CRP) levels were determined by an autoanalyzer using the manufacturer’s kits. Plasma von Willebrand factor antigen (VWF:Ag) levels were quantified by ELISA, and plasma fibronectin concentration by nephelometry. The amount of cell-free fetal DNA in maternal plasma was determined by quantitative real-time polymerase chain reaction analysis of the sex-determining region Y gene. Plasma malondialdehyde levels were measured by the thiobarbituric acid-based colorimetric assay. Serum Hsp70 levels were increased in preeclampsia. Furthermore, serum levels of blood urea nitrogen, creatinine, bilirubin and CRP, serum alanine aminotransferase and lactate dehydrogenase (LDH) activities, as well as plasma levels of VWF:Ag, fibronectin, cell-free fetal DNA and malondialdehyde were also significantly higher in preeclamptic patients than in normotensive, healthy pregnant women. In preeclamptic patients, serum Hsp70 levels showed significant correlations with serum CRP levels (Spearman R = 0.32, p = 0.010), serum aspartate aminotransferase (R = 0.32, p = 0.008) and LDH activities (R = 0.50, p < 0.001), as well as with plasma malondialdehyde levels (R = 0.25, p = 0.043). However, there was no other relationship between serum Hsp70 levels and clinical characteristics (age, parity, body mass index, blood pressure, gestational age, fetal birth weight) and laboratory parameters of preeclamptic patients, including markers of endothelial activation or injury and trophoblast debris. In conclusion, increased serum Hsp70 levels seem to reflect systemic inflammation, oxidative stress and hepatocellular injury in preeclampsia. Nevertheless, further studies are required to determine whether circulating Hsp70 plays a causative role in the pathogenesis of the disease.     

Effects of acetylsalicylic acid treatment on thyroid hormones,prolactins, and the stress response of tilapia (Oreochromis mossambicus)

The cyclooxygenase (COX) pathway converts arachidonic acid (ArA) into prostaglandins (PGs), which interact with the stress response in mammals and possibly in fish as well. Acetylsalicylic acid (ASA) is a COX inhibitor and was used to characterize the effects of PGs on the release of several hormones and the stress response of tilapia (Oreochromis mossambicus). Plasma PGE2 was significantly reduced at 100 mg ASA/kg body wt, and both basal PGE2 and cortisol levels correlated negatively with plasma salicylate. Basal plasma 3,5,3'-triiodothyronine (T3) was reduced by ASA treatment, whereas prolactin (PRL)188 increased at 100 mg ASA/kg body wt. ASA depressed the cortisol response to the mild stress of 5 min of net confinement. As expected, glucose and lactate were elevated in the stressed control fish, but the responses were blunted by ASA treatment. Gill Na+-K+-ATPase activity was not affected by ASA. Plasma osmolarity increased after confinement in all treatments, whereas sodium only increased at the high ASA dose. This is the first time ASA has been administered to fish in vivo, and the altered hormone release and the inhibition of the acute stress response indicated the involvement of PGs in these processes.     

CCDC115 Deficiency Causes a Disorder of Golgi Homeostasis with Abnormal Protein Glycosylation

Disorders of Golgi homeostasis form an emerging group of genetic defects. The highly heterogeneous clinical spectrum is not explained by our current understanding of the underlying cell-biological processes in the Golgi. Therefore, uncovering genetic defects and annotating gene function are challenging. Exome sequencing in a family with three siblings affected by abnormal Golgi glycosylation revealed a homozygous missense mutation, c.92T>C (p.Leu31Ser), in coiled-coil domain containing 115 (CCDC115), the function of which is unknown. The same mutation was identified in three unrelated families, and in one family it was compound heterozygous in combination with a heterozygous deletion of CCDC115. An additional homozygous missense mutation, c.31G>T (p.Asp11Tyr), was found in a family with two affected siblings. All individuals displayed a storage-disease-like phenotype involving hepatosplenomegaly, which regressed with age, highly elevated bone-derived alkaline phosphatase, elevated aminotransferases, and elevated cholesterol, in combination with abnormal copper metabolism and neurological symptoms. Two individuals died of liver failure, and one individual was successfully treated by liver transplantation. Abnormal N- and mucin type O-glycosylation was found on serum proteins, and reduced metabolic labeling of sialic acids was found in fibroblasts, which was restored after complementation with wild-type CCDC115. PSI-BLAST homology detection revealed reciprocal homology with Vma22p, the yeast V-ATPase assembly factor located in the endoplasmic reticulum (ER). Human CCDC115 mainly localized to the ERGIC and to COPI vesicles, but not to the ER. These data, in combination with the phenotypic spectrum, which is distinct from that associated with defects in V-ATPase core subunits, suggest a more general role for CCDC115 in Golgi trafficking. Our study reveals CCDC115 deficiency as a disorder of Golgi homeostasis that can be readily identified via screening for abnormal glycosylation in plasma.     

Effects of thermal stress on plasma concentrations of luteinizing hormone, progesterone, prolactin and testosterone in the cycling ewe

Naturally cycling white faced ewes were utilized to study the effects of continuously elevated environmental temperature and/or humidity on plasma concentrations of luteinizing hormone (LH), prolactin (PRL), progesterone (P4) and testosterone (TE) during the estrous cycle. Fourteen ewes were randomly allocated on the day of estrus (day 0) to either thermoneutral conditions (21.1 degrees C, 65% relative humidity) or elevated ambient temperature/humidity conditions (36.1 degrees C, 71% relative humidity) producing an average 1.4 degrees C hyperthermia. Animals remained in their respective environments and blood samples were collected daily until the next estrus or day 20, whichever occurred first. Starting at noon on day 14, blood was sampled every 2 hours. Concentrations of LH, PRL, P4 and TE were quantified using validated radioimmunoassays. Hyperthermic ewes exhibited 1) a significant decrease (P<0.05) in the incidence of behavioral estrus and a preovulatory LH surge at the expected time of the estrous cycle, 2) significantly lower (P<0.05) plasma P4 between days 7 and 13 of the cycle, 3) a six-fold increase of PRL levels (P<0.01). Plasma levels of TE were not significantly affected by hyperthermia. The only two experimental ewes which exhibited estrus and an LH surge also showed an unusual and significant peak in plasma P4 two days before estrus. These results confirm that elevated environmental temperatures that result in hyperthermia can induce endocrine imbalances in the ewe which may contribute to decreased reproductive efficiency in the heat-stressed female.     

Epinephrine, norepinephrine, and cortisol concentrations in cannulated seawater-acclimated rainbow trout (Oncorhynchus mykiss) following black-box confinement and epinephrine injection

The present study investigates the effect of cannulation and chronic'black-box' confinement, as well as epinephrine administration (4–0 μg kg⁻¹), on the degree and time-course of alterations in trout ( Oncorhynchus mykiss ) catecholamine and cortisol concentrations. Plasma cortisol concentrations in seawater trout acclimated to 3–6° C reached 104 ng ml⁻¹ 1 day after cannulation/confinement and remained elevated above resting levels (8 ng ml⁻¹) until 6 days post-confinement. Although plasma epinephrine and norepinephrine generally declined over the period of confinement (day 1 approx. 12 nM; day 7 approx. 6 nM), norepinephrine titres were usually higher and more variable. Epinephrine injection caused elevations in plasma epinephrine levels but not in norepinephrine levels; epinephrine titres reaching 107 ± 26 nM (range 65–238 nM) at 2 min post-injection and returning to pre-injection levels by 30 min post-injection. Plasma cortisol increased by 20 ng ml⁻¹ following epinephrine administration. Based on the time-course for post-confinement alterations in plasma cortisol, it appears that up to a week may be required before cannulated fish are completely acclimated to 'black-box' confinement. The findings suggest that meaningful results from experiments utilizing epinephrine injection and 'black-box confinement are contingent upon: (1) knowledge of circulating epinephrine levels shortly after injection (i.e. within 2 min post-injection); and (2) an experimental design that takes into account the elevated cortisol titres that are inherent with cannulation/confinement and epinephrine injection.