[Activity of aromatic pyrrole-based compounds against of Schistosoma japonicum cercariae and acute toxicity to fish].

OBJECTIVE: To test the activity of aromatic pyrrole-based compounds against cercariae of Schistosoma japonicum and test their acute toxicity to fish. METHODS: A series of aromatic pyrrole-based compounds were synthesized using 4-benzyl-5-(trifluoromethyl)-1H-pyrrole-3-nitrile as the lead compound. The synthesized compounds were prepared into solutions at concentrations of 10.00, 1.00, 0.10, 0.01 mg/L, and the activity of these solutions against S. japonicum cercariae was tested in 30 min, while 0.10 mg/L and 0.01 mg/L niclosamide solutions served as a positive control and dechlorinated water with 1% dimethyl sulfoxide (DMSO) was used as a negative control, with 10 to 30 cercariae of S. japonicum in each group. In addition, the compounds were prepared into solutions at concentrations of 0.50, 0.25, 0.12, 0.06, 0.03 mg/L, and their toxicity to zebrafish was tested in 72 h, while 0.15 mg/L and 0.30 mg/L niclosamide solutions served as a positive control and dechlorinated water with 1% DMSO was used as a negative control, with 10 zebrafishes in each group. RESULTS: A total of 7 aromatic pyrrole-based compounds were successfully synthesized. Treatment with compounds 102, 104 and 106 at a concentration of 0.01 mg/L for 30 min killed all S. japonicum cercariae, and compounds 105 and 107 showed no activity against cercariae. No death of cercariae was found in the blank control group, while treatment with 0.10 mg/L niclosamide for 10 min caused a 100% mortality rate of S. japonicum cercariae and 0.01 mg/L niclosamide failed to kill S. japonicum cercariae. No zebrafish death was found 72 h post-treatment with compounds 101, 104 and 105 at a concentration of 0.03 mg/L, and exposure to compounds 102, 103 and 106 at a concentration of 0.03 mg/L for 12 h resulted in a 100% mortality rate of zebrafish. No zebrafish death occurred 72 h post-treatment with 0.50 mg/L Compound 104, and no zebrafish death was found in the blank control group, while treatment with 0.30 mg/L niclosamide for 24 h resulted in a 100% mortality rate of zebrafish. CONCLUSIONS: Compound 104 achieves a 100% mortality rate against S. japonicum cercariae at a concentration of 0.01 mg/L for 30 min, and causes no death of zebrafish at a concentration of 0.50 mg/L for 72 h, which may serve as a cercaricide candidate.

[Molluscicidal activity of the secondary metabolites from Streptomyces nigrogriseolus XD 2-7 against Oncomelania hupensis and its preliminary mechanisms of molluscicidal actions].

OBJECTIVE: To evaluate the storage stability of metabolites from actinomycetes Streptomyces nigrogriseolus XD 2-7 and the mollcuscicidal activity against Oncomelania hupensis in the laboratory, and to preliminarily explore the mechanisms of the molluscicidal activity. METHODS: The fermentation supernatant of S. nigrogriseolus XD 2-7 was prepared and stored at -20, 4 °C and 28 °C without light for 10 d; then, the molluscicidal effect was tested against O. hupensis following immersion for 72 h. The fermentation supernatant was boiled in a 100 °C water bath for 30 min and recovered to room temperature, and then the molluscicidal effect was tested against O. hupensis following immersion for 72 h. The pH values of the fermentation supernatant were adjusted to 4.0, 6.0 and 9.0 with concentrated hydrochloric acid and sodium hydroxide, and the fermentation supernatant was stilled at room temperature for 12 h, with its pH adjusted to 7.0; then, the molluscicidal effect was tested against O. hupensis following immersion for 72 h. The fermentation product of S. nigrogriseolus XD 2-7was isolated and purified four times with macroporous resin, silica gel and octadecylsilane bonded silica gel. The final products were prepared into solutions at concentrations of 10.00, 5.00, 2.50, 1.25 mg/L and 0.63 mg/L, and the molluscicidal effect of the final productswas tested against O. hupensis following immersion for 72 h, while dechlorination water served as blank controls, and 0.10 mg/L niclosamide served as positive control. The adenosine triphosphate (ATP) and adenosine diphosphate (ADP) levels were measured in in O. hupensis soft tissues using high performance liquid chromatography (HPLC) following exposure to the final purified fermentation products of S. nigrogriseolus XD 2-7. RESULTS: After the fermentation supernatant of S. nigrogriseolus XD 2-7 was placed at -20, 4 °C and 28 °C without light for 10 d, immersion in the stock solution and solutions at 10- and 50-fold dilutions for 72 h resulted in a 100% (30/30) O. hupensis mortality. Following boiling at 100 °C for 30 min, immersion in the stock solution and solutions at 10- and 50-fold dilutions for 72 h resulted in a 100.00% (30/30) O. hupensis mortality. Following storage at pH values of 4.0 and 6.0 for 12 h, immersion in the fermentation supernatant of S. nigrogriseolus XD 2-7 for 72 h resulted in a 100.00% (30/30) O. hupensis mortality, and following storage at a pH value of 9.0 for 12 h, immersion in the fermentation supernatant of S. nigrogriseolus XD 2-7 for 72 h resulted in a 33.33% (10/30) O. hupensis mortality (χ2 = 30.000, P < 0.05). The minimum concentration of the final purified fermentation products of S. nigrogriseolus XD 2-7 was 1.25 mg/L for achieving a 100% (30/30) O. hupensis mortality. The ATP level was significantly lower in O. hupensis soft tissues exposed to 0.10 mg/L and 1.00 mg/L of the final purified fermentation products of S. nigrogriseolus XD 2-7 than in controls (F = 7.274, P < 0.05), while no significant difference was detected in the ADP level between the treatment group and controls (F = 2.485, P > 0.05). CONCLUSIONS: The active mollcuscicidal ingredients of the S. nigrogriseolus XD 2-7 metabolites are maintained stably at -20, 4 °C and 28 °C for 10 d, and are heat and acid resistant but not alkali resistant. The metabolites from S. nigrogriseolus XD 2-7 may cause energy metabolism disorders in O. hupensis, leading to O. hupensis death.

[Effects of praziquantel isomers on the proliferation and activation of the LX-2 human hepatic stellate cell line].

OBJECTIVE: To compare the effects of levo-praziquantel (L-PZQ) and dextro-praziquantel (D-PZQ) on the proliferation and activation of the human hepatic stellate cell line LX-2 in vitro. METHODS: LX-2 cells were stimulated with transforming growth factor-ß (TGF-ß). LX-2 cell proliferation was measured using the CCK-8 assay after 24 h stimulation with 0 to 50 µg/mL concentrations of praziquantel, and the gene and protein expression of type Ⅰ collagen (collagen Ⅰ), type Ⅲ collagen (collagen Ⅲ) and α-smooth muscle actin (α-SMA) was quantified in LX-2 cells using quantitative real-time PCR (qPCR) and Western blotting assays 24 h and 48 h following stimulation with 15 µg/mL praziquantel to detect LX-2 cell activation. RESULTS: There were significant differences in the survival rate of LX-2 cells between L-PZQ and D-PZQ treatments at all concentrations (F = 6.119 and 79.180, both P values < 0.05). Either L-PZQ or D-PZQ at a concentration of < 30 µg/mL showed no remarkableeffectsonthe LX-2 cell proliferation (both P values > 0.05), and L-PZQ at a concentration of > 50 µg/mL and D-PZQ at a concentration of > 40 µg/mL inhibited the LX-2 cell proliferation (both P values < 0.05), while D-PZQ at concentrations of 40 µg/mL and 50 µg/mL showed greater inhibition on LX-2 cell proliferation than L-PZQ (t = 3.419 and 8.776, both P values < 0.05). There were significant differences in the collagen Ⅰ, collagen Ⅲ and α-SMA expression in LX-2 cells at both transcriptional (F = 21.55, 79.99 and 46.70, all P values < 0.05) and translational levels (F = 20.12, 30.29 and 32.93, all P values < 0.05) among the blank control group, TGF-ß stimulation group, L-PZQ treatment group and D-PZQ treatment group. L-PZQ treatment resulted in remarkable inhibition on collagen Ⅲ and α-SMA gene expression in LX-2 cells (both P values < 0.05); however, the treatment showed no remarkable inhibition collagen Ⅰ gene expression or collagen Ⅰ, collagen Ⅲ or α-SMA protein expression in LX-2 cells (all P values > 0.05). In addition, D-PZQ treatment resulted in significant inhibition on collagen Ⅰ, collagen Ⅲ and α-SMA expression in LX-2 cells at both translational and transcriptional levels (all P values < 0.05), and D-PZQ showed higher inhibition on collagen Ⅰ, collagen Ⅲ and α-SMA gene expression in LX-2 cells than L-PZQ (all P values < 0.05). CONCLUSIONS: Both L-PZQ and D-PZQ inhibit the proliferation and activation of LX-2 cells, and D-PZQ shows a higher inhibitory activity than L-PZQ.

Altered interactions of tryptophan metabolites in first-episode neuroleptic-naive patients with schizophrenia.

Schizophrenia is characterized by complex and dynamically interacting perturbations in multiple neurochemical systems. In the past, evidence for these alterations has been collected piecemeal, limiting our understanding of the interactions among relevant biological systems. Earlier, both hyper- and hyposerotonemia were variously associated with the longitudinal course of schizophrenia, suggesting a disturbance in the central serotonin (5-hydroxytryptamine (5-HT)) function. Using a targeted electrochemistry-based metabolomics platform, we compared metabolic signatures consisting of 13 plasma tryptophan (Trp) metabolites simultaneously between first-episode neuroleptic-naive patients with schizophrenia (FENNS, n=25) and healthy controls (HC, n=30). We also compared these metabolites between FENNS at baseline (BL) and 4 weeks (4w) after antipsychotic treatment. N-acetylserotonin was increased in FENNS-BL compared with HC (P=0.0077, which remained nearly significant after Bonferroni correction). N-acetylserotonin/Trp and melatonin (Mel)/serotonin ratios were higher, and Mel/N-acetylserotonin ratio was lower in FENNS-BL (all P-values<0.0029), but not after treatment, compared with HC volunteers. All three groups had highly significant correlations between Trp and its metabolites, Mel, kynurenine, 3-hydroxykynurenine and tryptamine. However, in the HC, but in neither of the FENNS groups, serotonin was highly correlated with Trp, Mel, kynurenine or tryptamine, and 5-hydroxyindoleacetic acid (5HIAA) was highly correlated with Trp, Mel, kynurenine or 3-hydroxykynurenine. A significant difference between HC and FENNS-BL was further shown only for the Trp-5HIAA correlation. Thus, some metabolite interactions within the Trp pathway seem to be altered in the FENNS-BL patients. Conversion of serotonin to N-acetylserotonin by serotonin N-acetyltransferase may be upregulated in FENNS patients, possibly related to the observed alteration in Trp-5HIAA correlation. Considering N-acetylserotonin as a potent antioxidant, such increases in N-acetylserotonin might be a compensatory response to increased oxidative stress, implicated in the pathogenesis of schizophrenia.

[Impact of Buruli ulcer secondary prevention program in an endemic area in Côte d'Ivoire]. / Effets d'un programme de prévention secondaire de l'ulcère de Buruli dans une zone d'endémie d'ulcère de Buruli en Côte d'Ivoire.

Mycobacterium ulcerans infection or Buruli ulcer begins by a papule, nodule, blotch or oedema and develops into ulceration with complications which can lead to disabilities. Its prevalence is high in West Africa and in Côte d'Ivoire particularly. Until recently, only ulcerated forms were mostly observed, whereas nodular ones were unnoticed or did not draw patients' attention. From 1999 to 2002 we conducted a before-after survey in the endemic area of Zoukougbeu located in Daloa region, the central west part of Côte d'Ivoire in order to assess the potential impact of a screening and treatment strategy for nodular forms of Buruli ulcer on ulceration rate decrease. The survey used clinical criteria necessary to identify Buruli ulcer nodule which were defined according to a former study carried out in the same area in 1998. As result of our survey 781 Buruli ulcer cases were reported of which 34.7% were ulcerative forms, 61.1% were nodules and 4.2% were other forms (blotch and oedema). By comparing the data of 1999, when the prevention program started, to those of 2002, we observed a drop of 47.6% in the ulcerative lesions and an increase of 57.4% in nodule ones. These changes were statistically significant (p < 10-5). Annual trend, from 1999 to 2002, showed a decrease in the detection rate of the respective forms under study. It ranged from 25.8/10000 to 7.3/10000 for ulcerative lesions and from 23/10000 to 19.7/10000 for nodules. In spite of possible defects in the methodology of a before/after survey the incidence decrease of both ulcerative and nodular forms that coincided with the prevention program probably reflects the efficacy of the secondary prevention program that promotes early diagnosis and treatment of nodular forms of Mycobacterium ulcerans infection.

Therapeutic efficacy of atypical antipsychotic drugs by targeting multiple stress-related metabolic pathways.

Schizophrenia (SZ) is considered to be a multifactorial brain disorder with defects involving many biochemical pathways. Patients with SZ show variable responses to current pharmacological treatments of SZ because of the heterogeneity of this disorder. Stress has a significant role in the pathophysiological pathways and therapeutic responses of SZ. Atypical antipsychotic drugs (AAPDs) can modulate the stress response of the hypothalamic-pituitary-adrenal (HPA) axis and exert therapeutic effects on stress by targeting the prefrontal cortex (PFC) and hippocampus. To evaluate the effects of AAPDs (such as clozapine, risperidone and aripiprazole) on stress, we compared neurochemical profile variations in the PFC and hippocampus between rat models of chronic unpredictable mild stress (CUMS) for HPA axis activation and of long-term dexamethasone exposure (LTDE) for HPA axis inhibition, using an ultraperformance liquid chromatography-mass spectrometry (UPLC-MS/MS)-based metabolomic approach and a multicriteria assessment. We identified a number of stress-induced biomarkers comprising creatine, choline, inosine, hypoxanthine, uric acid, allantoic acid, lysophosphatidylcholines (LysoPCs), phosphatidylethanolamines (PEs), corticosterone and progesterone. Specifically, pathway enrichment and correlation analyses suggested that stress induces oxidative damage by disturbing the creatine-phosphocreatine circuit and purine pathway, leading to excessive membrane breakdown. Moreover, our data suggested that the AAPDs tested partially restore stress-induced deficits by increasing the levels of creatine, progesterone and PEs. Thus, the present findings provide a theoretical basis for the hypothesis that a combined therapy using adenosine triphosphate fuel, antioxidants and omega-3 fatty acids as supplements may have synergistic effects on the therapeutic outcome following AAPD treatment.

[Fighting against Buruli ulcer: the Côte-d'Ivoire experience]. / La lutte contre l'ulcère de Buruli. experience de la Côte-d'Ivoire.

Caused by Mycobacterium ulcerans, Buruli ulcer is an infectious disease which leads to large cutaneous ulceration and is responsible for huge socio-economic consequences. Since 1997 the World Health Organization has started a global Buruli ulcer initiative in which African endemic countries are committed. After an epidemiological background of the disease in Côte-d'Ivoire and a description of the different clinical aspects, we report the main disease management actions carried out in the country by the National Program for Buruli ulcer control from 1998 to 2003. It seems that surgical team missions carried out in health center to treat cases, early detection and treatment of cases together with the implementation of a specific poly-chemotherapy lead to an effective control of the disease.

Structural alterations of peripheral nerve monogalactosylceramides during development and Wallerian degeneration.

The structural alterations of monogalactosylceramides in peripheral nerve were investigated during development, nerve fiber degeneration and regeneration. During early development, hydroxy cerebrosides and sulfatides were the main constituents of the monogalactosylceramides of immature rat sciatic endoneurium. The ratio of hydroxy to nonhydroxy cerebrosides decreased rapidly as myelination proceeded but remained fairly constant throughout adulthood. More than 50% of the adult content of endoneurial monogalactosylceramides was achieved before 21 days of age. The long-chain nonhydroxy fatty acids (above C21) had increased from under 20% to over 80% by day 20, while 24h:0 (h, hydroxy) had already reached approximately 50% of hydroxy cerebrosides by day 12. These results suggest that the biosynthesis of endoneurial monogalactosylceramides and fatty acid elongation take place preferentially at the time when peripheral nerve is undergoing active myelination. During Wallerian degeneration, the maximum decrease of monogalactosylceramides was associated temporally with axonal degeneration and demyelination and particularly with myelin conversion to sudanophilic lipids. By the time that nerve fiber regeneration was well established, both the cerebroside and sulfatide contents had returned to near control values. Cerebrosides and long-chain fatty acids (above C21) appear to be the most sensitive to fiber degeneration while fatty acid elongation is selectively increased during nerve regeneration.

Increased polyunsaturated fatty acids in developing and regenerating peripheral nerve.

Characteristic fatty acids of peripheral nerve myelin are mainly saturated and monounsaturated. A marked increase of polyunsaturated fatty acids, particularly arachidonic acid, was found in endoneurial phosphatidylethanolamine of both developing and regenerating rat sciatic nerve, suggesting a close association between polyunsaturated fatty acids and peripheral nerve myelination.

[14C]acetate metabolism in the peripheral nervous system.

Lipid biosynthesis was studied by incorporation of [14C]acetate into different compartments of rat sciatic nerve during development, degeneration and regeneration. Acetate incorporation was over three times higher in the sciatic endoneurium (desheathed nerve) than in epi- and perineurium. The endoneurium contained much higher contents of radioactively labeled membrane lipids (cholesterol and phospholipids) than did the epi- and perineurium (mainly triacylglycerol), indicating a benefit of utilization of endoneurium in the study of the metabolic derangements of peripheral nerve lipids. When 3H2O was used as a precursor, no incorporation was found. Endoneurial lipid biosynthesis from [14C]acetate decreased rapidly as myelination proceeded. After 4 months, the decrease continued but at a much slower rate. The total acetate incorporation found in endoneurial lipids of 6-month-old rats was predominantly in the free fatty acid fraction (40%), but was only 5% of that found in 10-day-old rats, demonstrating the importance of age-matched controls for metabolic studies of diseased nerve. During Wallerian degeneration, a decreased acetate incorporation into endoneurial lipids was observed as early as 2 days after crush injury. The profile of labeled lipids in developing and degenerating nerve revealed that the rate of lipogenesis did not change to the same extent for each lipid subclass. Cholesterol biosynthesis appeared to be the most sensitive. During regeneration, an increase in the uptake of [14C]acetate and an altered profile of labeled lipids demonstrated that the metabolic state of adult peripheral nerve, which is normally relatively inactive, can be modified by an exogenous factor such as crush injury.

Structural specificity in demyelination induced by lysophospholipids.

The demyelinating activity of lysophosphatidylcholine (lysoPC) and various structural analogs in rat sciatic nerve was evaluated by following electrophysiologic changes within the first hour and 1 week after intraneural injection. The lysophospholipids tested included 1-O-hexadecanoyl-sn-glycero-3-phosphocholine (1-acyl-GPC), 3-O-hexadecanoyl-sn-glycero-1-phosphocholine (3-acyl-GPC), 1-O-hexadecanoylpropanediol-3-phosphocholine (acyl-PPC), 1-O-hexadecylpropanediol-3-phosphocholine (alkyl-PPC) and 1-acyl-sn-glycero-3-phosphoethanolamine (1-acyl-GPE). Changes in conduction velocity, width, amplitude and time integral percentage were measured. Within 1 hour, the highest demyelinating activity was observed for alkyl-PPC, followed by 3-acyl-GPC, 1-acyl-GPC and acyl-PPC. Hydrolysis products of lysoPC (glycerophosphocholine, fatty acid), lysophosphatidylethanolamine (1-acyl-GPE), biradyl choline phospholipids (1,2-di-O-alkyl-rac-glycero-3-phosphocholine, dialkyl-GPC) or sodium deoxycholate proved ineffective in these short-term experiments. One week after intraneural injection, all lysophospholipids tested caused severe electrophysiologic changes, although dialkyl-GPC and sodium deoxycholate did not. Our data suggest (i) that differences in early demyelinating activity by the choline lysophospholipids are related to their rate of turnover, as highest activity was associated with the agents that are not metabolized by lysophospholipase (e.g., alkyl-PPC) or lysolecithin acyltransferase (e.g., 3-acyl-GPC), (ii) that the lysoPC molecule as such and not its products of catabolism causes demyelination, and (iii) that demyelinating activity is not due to the general detergent action of lysoPC, but rather that specific interactions appear to trigger the processes of demyelination induced by lysophospholipids.

Alpha-lipoic acid: effect on glucose uptake, sorbitol pathway, and energy metabolism in experimental diabetic neuropathy.

The peripheral nerve of experimental diabetic neuropathy (EDN) is reported to be ischemic and hypoxic, with an increased dependence on anaerobic metabolism, requiring increased energy substrate stores. When glucose stores become reduced, fiber degeneration has been reported. We evaluated glucose uptake, nerve energy metabolism, the polyol pathway, and protein kinase C (PKC) activity in EDN induced by streptozotocin. Control and diabetic rats received lipoic acid (0, 10, 25, 50, 100 mg/kg). Duration of diabetes was 1 month, and alpha-lipoic acid was administered intraperitoneally 5 times per week for the final week of the experiment. Nerve glucose uptake was reduced to 60, s 37, and 30% of control values in the sciatic nerve, L5 dorsal root ganglion, and superior cervical ganglion (SCG), respectively, in rats with EDN. Alpha-lipoic acid supplementation had no effect on glucose uptake in normal nerves at any dose, but reversed the deficit in EDN, with a threshold between 10 and 25 mg/kg. Endoneurial glucose, fructose, sorbitol, and myo-inositol were measured in sciatic nerve. Alpha-lipoic acid had no significant effect on either energy metabolism or polyol pathway of normal nerves. In EDN, endoneurial glucose, fructose, and sorbitol were significantly increased, while myo-inositol was significantly reduced. Alpha-lipoic acid had a biphasic effect: it dose-dependently increased fructose, glucose, and sorbitol, peaking at 25 mg/kg, and then fell beyond that dose, and it dose-dependently increased myo-inositol. Sciatic nerve cytosolic PKC was increased in EDN. ATP, creatine phosphate, and lactate were measured in sciatic nerve and SCG. Alpha-lipoic acid prevented the reduction in SCG creatine phosphate. We conclude that glucose uptake is reduced in EDN and that this deficit is dose-dependently reversed by alpha-lipoic acid, a change associated with an improvement in peripheral nerve function.

Behavioral vs biochemical prediction of clinical stability following haloperidol withdrawal in schizophrenia.

BACKGROUND: We sought to identify haloperidol-treated subjects who relapsed within 6 weeks of placebo replacement and those who did not, using multivariate analysis. METHODS: In the week prior to discontinuation of haloperidol treatment, global behavioral ratings and a lumbar puncture for cerebrospinal fluid monoamine metabolities were obtained in 88 patients with chronic schizophrenia. Logistic regression analyses were used to evaluate two competing models of relapse prediction. The models were then compared using receiver operating characteristic analysis and a final combined model was derived. RESULTS: The behavioral model was less variable in its prediction than the cerebrospinal fluid monoamine model. The final model consisted of increased psychosis, decreased anxiety, higher cerebrospinal fluid homovanillic acid levels, and lower cerebrospinal fluid 5-hydroxyindoleacetic acid levels. CONCLUSIONS: Several monoamine systems are involved in psychotic relapse within 6 weeks of haloperidol withdrawal. Future studies of relapse prediction should include both clinical and biological measures to fully assess relapse risk.

A potential mechanism underlying atypical antipsychotics-induced lipid disturbances.

Previous findings suggested that a four-protein complex, including sterol-regulatory element-binding protein (SREBP), SREBP-cleavage-activating protein (SCAP), insulin-induced gene (INSIG) and progesterone receptor membrane component 1 (PGRMC1), within the endoplasmic reticulum appears to be an important regulator responsible for atypical antipsychotic drug (AAPD)-induced lipid disturbances. In the present study, effects of typical antipsychotic drug and AAPDs as well as treatment outcome of steroid antagonist mifepristone (MIF) on the PGRMC1/INSIG/SCAP/SREBP pathway were investigated in rat liver using real-time quantitative polymerase chain reaction (qPCR) and western blot analysis. In addition, serum triacylglycerol, total cholesterol, free fatty acids and various hormones including progesterone, corticosterone and insulin were measured simultaneously. Following treatment with clozapine or risperidone, both lipogenesis and cholesterogenesis were enhanced via inhibition of PGRMC1/INSIG-2 and activation of SCAP/SREBP expressions. Such metabolic disturbances, however, were not demonstrated in rats treated with aripiprazole (ARI) or haloperidol (HAL). Moreover, the add-on treatment of MIF was effective in reversing the AAPD-induced lipid disturbances by upregulating the expression of PGRMC1/INSIG-2 and subsequent downregulation of SCAP/SREBP. Taken together, our findings suggest that disturbances in lipid metabolism can occur at an early stage of AAPD treatment before the presence of weight gain. Such metabolic defects can be modified by an add-on treatment of steroid antagonist MIF enhancing the PGRMC1 pathway. Thus, it is likely that PGRMC1/INSIG-2 signaling may be a therapeutic target for AAPD-induced weight gain.

Adult-onset of Tangier disease: 1. Morphometric and pathologic studies suggesting delayed degradation of neutral lipids after fiber degeneration.

A 67-year-old woman, with the typical biochemical features of Tangier disease, had a syringomyelia-like syndrome which has now been observed in several patients with symptomatic onset in adult life. She developed progressive facial diplegia, bilateral wasting of hand muscles and loss of sensation over cranial, cervical and brachial dermatomes over 17 years. Nociception alone was first affected, then nociception and thermal discrimination and finally all modalities of sensation. Quantified tests of cutaneous sensation confirmed that sensation was normal in lower limbs but markedly abnormal in upper limbs. Biopsied fascicles of cutaneous nerves from clinically affected (forearm) and from clinically unaffected (leg) regions permitted a comparison of well-advanced and early pathologic lesions, respectively. The selective vulnerability of unmyelinated and small myelinated fibers in affected regions in this disorder has been confirmed. The earliest morphologic abnormalities of myelinated fibers, but seen infrequently, were mitochondrial enlargement and structural abnormality, aggregation of mitochondria and dense bodies and clusters of neurofilaments. Increased numbers of sudanophilic lipid droplets did not seem to form in Schwann cell cytoplasm prior to fiber degeneration. On the contrary, for myelinated fibers there appeared to be an altered process of axonal degeneration from that seen in Wallerian degeneration and in other axonal degenerations. Distinctive linear bands of closely-packed, minute, osmiophilic and clear lipid droplets formed and their further degradation appeared delayed. Although less clearly demonstrated, lipid droplets in Schwann cells of unmyelinated fibers also appeared to form following their degeneration. We would propose that in Tangier disease, the degradation of myelin ovoids to neutral lipid in Schwann cells does not appear to be delayed. However, further degradation of neutral lipid or its transport away from Schwann cells appears to be retarded.

Structural and biochemical effects of essential fatty acid deficiency on peripheral nerve.

The effect of postweaning essential fatty acid (EFA) deficiency on the peripheral nerve was studied in groups of rats. At 325 days, the characteristic biochemical changes of EFA deficiency were present in isolated peripheral myelin, although to a lesser degree than reported in non-neural tissues. There was no significant difference between control and deficient groups in number or size distributions of myelinated fibers (MFs) in muscle and sensory nerves, in the incidence of teased fiber abnormalities, in rates of axonal transport of dopamine-beta-hydroxylase and acetylcholinesterase, or in conduction velocity and compound action potentials of peripheral nerve in vivo or in vitro. Four weeks after a standard sciatic crush injury, the median MF diameter in regenerated peroneal nerves was significantly smaller in EFA-deficient rats than in control rats, but this difference was no longer significant at 18 weeks. At 18 weeks, EFA-deficient and control regenerated nerves showed similar myelin periodicity and relationship of axonal area to number of myelin lamellae. We conclude that acquired EFA deficiency in the rat leads to biochemically abnormal peripheral myelin, but that this state is unaccompanied by clinical, physiological, or morphological evidence of neuropathy.

Biochemical studies in a patient with a Tangier syndrome.

The chemical composition of the major classes of lipids were evaluated in the plasma and in various other tissues of a 68-year-old woman with a syringomyelia-like syndrome affecting cranial, cervical and brachial regions. No tonsillar abnormalities were apparent on visual examination of the oropharynx but the absence of alpha-lipoproteins on serum lipoprotein electrophoresis prompted the tentative diagnosis of Tangier disease. The diagnosis was confirmed by lipid, lipoprotein and apolipoprotein analyses of the plasma. The plasma cholesterol was low (93-113 mg/dl) and the triglyceride concentration normal (133-160 mg/dl). The very low density lipoproteins had normal chemical composition and morphology, but migrated with beta rather than pre-beta mobility on paper electrophoresis. Low density lipoproteins were deficient in cholesteryl esters and enriched in triglycerides; their electrophoretic mobility and morphology were normal. A small amount of high density lipoprotein (approximately 1.4 mg/dl) was recovered from the plasma. This contained few particles of the size of normal high density lipoprotein and polyacrylamide gel electrophoresis of the lipid-free protein demonstrated a disproportionate increase in the A-II apolipoprotein. All of these abnormalities are consistent with Tangier disease. The serum concentration of glycosphingolipids was approximately 40% lower than normal, with the most marked reductions in the glucosylceramide (GL-1a) and trihexosylceramide (GL-3a) fractions. The relative quantity of long chain fatty acids (23 or more carbons) in serum sphingomyelin was reduced about 38% of that in control sera. Serum lecithin:cholesterol acyltransferase (EC 2.3.1.43; LCAT) activity was 25% of normal and the reduced activity was shown not to be related to a change of enzyme specificity or to a lack of appropriate substrate. These findings are likely related to the HDL deficiency which characterizes Tangier disease. A biopsy sample of apparently normal tonsil contained three to four times the normal amount of cholesterol, and the increase was due entirely to abnormal quantities of cholesteryl esters. Of great interest was the chemical documentation of increased cholesteryl esters in a nerve biopsy specimen. These findings indicate that the neurologic as well as the reticuloendothelial manifestations of Tangier disease may be related to cholesteryl ester accumulation. Lipoprotein profiles, their triglyceride and cholesterol concentration, and LCAT activity were obtained on the plasma of 7 closely related members of the kinship. None of these relatives were found to have the biochemical derangement of Tangier disease.

Platelet dense granule secretion in adolescents with conduct disorder and substance abuse: preliminary evidence for variation in signal transduction.

Platelet aggregation responses to agonists have been employed as peripheral indices of the physiological responsiveness and density of neurotransmitter receptors, and in investigations of membrane functioning in psychopathological conditions. In particular, there are mechanistic similarities between neuronal secretory and receptor dynamics, and those involved in platelet dense granule secretion. Consequently, we have explored the platelet dense granule secretory responses to various agonists in abstinent male adolescents who meet current psychiatric diagnostic criteria for Conduct Disorder and Psychoactive Substance. Use Disorder (CD+/PSUD+) in contrast to controls (CD-/PSUD-). The results showed a significant hyporesponsivity among experimental subjects to collagen, thrombin, adenosine diphosphate (ADP), ADP plus 0.2 microgram of serotonin, and ADP plus 1.0 microgram of serotonin. Only dense granule responses to arachidonic acid did not differentiate the groups. Taken together, the lack of agonist specificity suggests that a variation in signal transduction mechanisms could account for the observed reduction in dense granule secretion among CD+/PSUD+ adolescents. Association between dense granule secretory responses and substance use behavior, and comorbid psychiatric conditions are also examined.

Platelet dense granule secretion and aggregation in adolescents with conduct disorder: effects of marijuana use.

BACKGROUND: We had previously reported a decrease in agonist-induced platelet dense granule secretion in blood samples from male adolescents with and without Conduct Disorder (CD). In an augmented sample, we have now employed multivariate modeling to examine the simultaneous effects of CD and regular monthly alcohol and marijuana use on both the dense granule secretion and aggregation phases of agonist-induced platelet responses. METHODS: Blood samples were obtained from adolescents with and without a CD diagnosis. Platelet dense granule secretion and aggregation responses to a variety of agonists were examined in the laboratory. RESULTS: Significant multivariate interactions of CD status with regular marijuana use were found for responses to collagen, ADP alone, and ADP plus 0.2 microgram. of serotonin. Responses in platelets from youth with CD, but without regular marijuana use differed from other subjects. Multivariate main effects of marijuana use alone on platelet responses to arachidonic acid and ADP plus 1.0 microgram. of serotonin were found. No effects of alcohol use were found. CONCLUSIONS: The results demonstrate an interaction between CD and the effects of chronic marijuana use for several agonists in this platelet model system, and further support the possibility of a variation in signal transduction mechanisms in CD.

Human plasma glutathione peroxidase and symptom severity in schizophrenia.

BACKGROUND: Previous studies have shown impaired antioxidant defense system in schizophrenia, including alterations in glutathione peroxidase (GSH-Px) activity in erythrocytes. There exists a related enzyme, human plasma GSH-Px (hpGSH-Px), that has not been previously examined in schizophrenia. METHODS: An enzyme-linked immunoassay was used to determine hpGSH-Px levels in male schizophrenic patients (n = 39), using a within-subject, on-off haloperidol (HD) treatment design, compared with age- and gender-matched normal control subjects (n = 37). RESULTS: hpGSH-Px was not significantly different between normal control subjects and patients, consistent with our previous findings in erythrocyte GSH-Px. There were no significant treatment effects. hpGSH-Px was significantly and positively correlated with psychosis rating scores in patients both on and off HD treatment. CONCLUSIONS: Although not different from normal controls, hpGSH-Px levels in patients may reflect oxidative stress associated with greater psychosis severity. The present findings thus suggest that schizophrenic patients, without obvious increase of endogenous antioxidant enzymes (e.g., hpGSH-Px), may be at risk for oxidative damage.