ER-depletion lowering the 'hypothalamus-uterus-kidney' axis functions by perturbing the renal ERß/Ptgds signalling pathway.

Researchers have long assumed that systematic estrogen fading might contribute to the sustained progression of menopausal degenerate syndromes, although definitive evidence has not been presented. Whether such findings represent a causal contribution or are the result of opportunistic messengers sent from the reproductive system to the brain is also a vital question. We constructed a multiscale network of the ovariectomy (OVX) induced estrogen receptors depletion (ER-depletion) model and integrated targeted proteomic, targeted lipidomic, cytochemical, and histopathological data across three tissues from the ovariectomy rodent model. We found that compared to control rats, OVX rats showed increased renal and uterine prostaglandin D2 synthase (Ptgds) expression and decreased hypothalamic Ptgds expression, abnormal Ptgds metabolites, the degenerate renal function profiles and decreased cognitive ability (learning and memory) in Morris water maze test. Importantly, we observed a regulatory relationship among ER (particularly ERß), the degree of the pathological phenotype, learning behavior test and the 'hypothalamus-uterus-kidney (HUK) axis functions. Collectively, this study elucidates that ER depletion promoted HUK aging is mostly attributed to a renal ERß/Ptgds signalling imbalance.

Disruption of Intestinal Homeostasis and Intestinal Microbiota During Experimental Autoimmune Uveitis.

Purpose: We determine the changes in intestinal microbiota and/or disruptions in intestinal homeostasis during uveitis. Methods: Experimental autoimmune uveitis (EAU) was induced in B10.RIII mice with coadministration of interphotoreceptor retinoid-binding protein peptide (IRBP) and killed mycobacterial antigen (MTB) as an adjuvant. Using 16S rRNA gene sequencing, we looked at intestinal microbial differences during the course of uveitis, as well as intestinal morphologic changes, changes in intestinal permeability by FITC-dextran leakage, antimicrobial peptide expression in the gastrointstinal tract, and T lymphocyte prevalence before and at peak intraocular inflammation. Results: We demonstrate that increased intestinal permeability and antimicrobial peptide expression in the intestinal tract coincide in timing with increased effector T cells in the mesenteric lymph nodes, during the early stages of uveitis, before peak inflammation. Morphologic changes in the intestine were most prominent during this phase, but also occurred with adjuvant MTB alone, whereas increased intestinal permeability was found only in IRBP-immunized mice that develop uveitis. We also demonstrate that the intestinal microbiota were altered during the course of uveitis, and that some of these changes are specific to uveitic animals, whereas others are influenced by adjuvant MTB alone. Intestinal permeability peaked at 2 weeks, coincident with an increase in intestinal bacterial strain differences, peak lipocalin production, and peak uveitis. Conclusions: An intestinal dysbiosis accompanies a disruption in intestinal homeostasis in autoimmune uveitis, although adjuvant MTB alone promotes intestinal disruption as well. This may indicate a novel axis for future therapeutic targeting experimentally or clinically.

Effect of Hydrogen Sulfide on Kidney Injury in Rat Model of Crush Syndrome.

BACKGROUND: Acute kidney injury is the most serious complication of crush syndrome. Hydrogen sulfide (H2S) is an endogenously produced gaseous signaling molecule. It is involved in homeostatic functions, such as blood pressure control, apoptosis, oxidative stress, and inflammation. In this study, effects of H2S on kidney injury were investigated in a rat model of crush syndrome. METHODS: Rats were divided into six groups (n = 8): Sham (steril saline ip), crush (sterile saline ip), crush + NaHS (sodium hydrosulfide, an H2S donor) (100 µmol/kg ip). All these groups were also separated as 3 and 24 h after decompression. Crush injury was induced by 6 h of direct compression to both hindlimbs of anesthetized rats with blocks weighing 3.6 kg each sides, followed by 3 or 24 h of decompression. Kidney injury molecule-1, neutrophil gelatinase-associated lipocalin, tumor-necrotizing factor-α, transforming growth factor-ß, tissue total oxidant status, and total antioxidant status levels were measured in kidney homogenates 3 and 24 h after decompression. Serum creatine kinase, blood urea nitrogen, and creatinine levels were also measured. Apoptosis was assessed by TUNEL method. Bcl-2 was assessed by immunohistochemistry. Glomerular and tubular structures were also examined histopathologically. RESULTS: NaHS reduced kidney injury molecule-1, neutrophil gelatinase-associated lipocalin, tumor-necrotizing factor-α, transforming growth factor-ß, total oxidant status levels, and increased total antioxidant status levels in kidney 3 and 24 h after decompression. Serum urea, creatinine, and creatine kinase levels also reduced with NaHS. NaHS decreased renal damage and apoptosis in crush-related acute kidney injury. CONCLUSIONS: These results suggest that H2S could reduce crush-related acute kidney injury via anti-inflammatory, antioxidant, and antiapoptotic effects.

Targeting arachidonic acid pathway to prevent programmed hypertension in maternal fructose-fed male adult rat offspring.

Hypertension can be programmed in response to nutritional insults in early life. Maternal high-fructose (HF) intake induced programmed hypertension in adult male offspring, which is associated with renal programming and arachidonic acid metabolism pathway. We examined whether early treatment with a soluble epoxide hydrolase (SEH) inhibitor, 12-(3-adamantan-1-yl-ureido)-dodecanoic acid (AUDA) or 15-Deoxy-Δ12,14-prostagandin J2 (15dPGJ2) can prevent HF-induced programmed hypertension. Pregnant Sprague Dawley rats received regular chow or chow supplemented with fructose (60% diet by weight) during the whole period of pregnancy and lactation. Four groups of male offspring were studied: control, HF, HF+AUDA and HF+15dPGJ2. In HF+AUDA group, mother rats received AUDA 25 mg/L in drinking water during lactation. In the HF+15dPGJ2 group, male offspring received 15dPGJ2 1.5 mg/kg body weight by subcutaneous injection once daily for 1 week after birth. Rats were sacrificed at 12 weeks of age. Maternal HF-induced programmed hypertension is associated with increased renal protein level of SEH and oxidative stress, which early AUDA therapy prevents. Comparison of AUDA and 15dPGJ2 treatments demonstrated that AUDA was more effective in preventing HF-induced programmed hypertension. AUDA therapy increases angiotensin converting enzyme-2 (ACE2) protein levels and PGE2 levels in adult offspring kidney exposed to maternal HF. 15dPGJ2 therapy increases plasma asymmetric dimethylarginine (ADMA) levels and decreases L-arginine-to-ADMA ratio. Better understanding of the impact of arachidonic acid pathway, especially inhibition of SEH, on renal programming may aid in developing reprogramming strategy to prevent programmed hypertension in children exposed to antenatal HF intake.

Human lung fibroblasts produce proresolving peroxisome proliferator-activated receptor-γ ligands in a cyclooxygenase-2-dependent manner.

Human lung fibroblasts (HLFs) act as innate immune sentinel cells that amplify the inflammatory response to injurious stimuli. Here, we use targeted lipidomics to explore the hypothesis that HLFs also play an active role in the resolution of inflammation. We detected cyclooxygenase-2 (COX-2)-dependent production of both proinflammatory and proresolving prostaglandins (PGs) in conditioned culture medium from HLFs treated with a proinflammatory stimulus, IL-1ß. Among the proresolving PGs in the HLF lipidome were several known ligands for peroxisome proliferator-activated receptor-γ (PPARγ), a transcription factor whose activation in the lung yields potent anti-inflammatory, antifibrotic, and proresolving effects. Next, we used a cell-based luciferase reporter to confirm the ability of HLF supernatants to activate PPARγ, demonstrating, for the first time, that primary HLFs activated with proinflammatory IL-1ß or cigarette smoke extract produce functional PPARγ ligands; this phenomenon is temporally regulated, COX-2- and lipocalin-type PGD synthase-dependent, and enhanced by arachidonic acid supplementation. Finally, we used luciferase reporter assays to show that several of the PGs in the lipidome of activated HLFs independently activate PPARγ and/or inhibit NFκB. These results indicate that HLFs, as immune sentinels, regulate both proinflammatory and proresolving responses to injurious stimuli. This novel endogenous resolution pathway represents a new therapeutic target for globally important inflammatory diseases such as chronic obstructive pulmonary disease.

Development of a scintillation proximity binding assay for high-throughput screening of hematopoietic prostaglandin D2 synthase.

Prostaglandin D2 synthase (PGDS) catalyzes the isomerization of prostaglandin H2 (PGH2) to prostaglandin D2 (PGD2). PGD2 produced by hematopoietic prostaglandin D2 synthase (H-PGDS) in mast cells and Th2 cells is proposed to be a mediator of allergic and inflammatory responses. Consequently, inhibitors of H-PGDS represent potential therapeutic agents for the treatment of inflammatory diseases such as asthma. Due to the instability of the PGDS substrate PGH2, an in-vitro enzymatic assay is not feasible for large-scale screening of H-PGDS inhibitors. Herein, we report the development of a competition binding assay amenable to high-throughput screening (HTS) in a scintillation proximity assay (SPA) format. This assay was used to screen an in-house compound library of approximately 280,000 compounds for novel H-PGDS inhibitors. The hit rate of the H-PGDS primary screen was found to be 4%. This high hit rate suggests that the active site of H-PGDS can accommodate a large diversity of chemical scaffolds. For hit prioritization, these initial hits were rescreened at a lower concentration in SPA and tested in the LAD2 cell assay. 116 compounds were active in both assays with IC50s ranging from 6 to 807 nM in SPA and 82 nM to 10 µM in the LAD2 cell assay.

Epigallocatechin-3-Gallate Inhibition of Myeloperoxidase and Its Counter-Regulation by Dietary Iron and Lipocalin 2 in Murine Model of Gut Inflammation.

Green tea-derived polyphenol (-)-epigallocatechin-3-gallate (EGCG) has been extensively studied for its antioxidant and anti-inflammatory properties in models of inflammatory bowel disease, yet the underlying molecular mechanism is not completely understood. Herein, we demonstrate that EGCG can potently inhibit the proinflammatory enzyme myeloperoxidase in vitro in a dose-dependent manner over a range of physiologic temperatures and pH values. The ability of EGCG to mediate its inhibitory activity is counter-regulated by the presence of iron and lipocalin 2. Spectral analysis indicated that EGCG prevents the peroxidase-catalyzed reaction by reverting the reactive peroxidase heme (compound I:oxoiron) back to its native inactive ferric state, possibly via the exchange of electrons. Further, administration of EGCG to dextran sodium sulfate-induced colitic mice significantly reduced the colonic myeloperoxidase activity and alleviated proinflammatory mediators associated with gut inflammation. However, the efficacy of EGCG against gut inflammation is diminished when orally coadministered with iron. These findings indicate that the ability of EGCG to inhibit myeloperoxidase activity is one of the mechanisms by which it exerts mucoprotective effects and that counter-regulatory factors such as dietary iron and luminal lipocalin 2 should be taken into consideration for optimizing clinical management strategies for inflammatory bowel disease with the use of EGCG treatment.

Growth inhibitory effect of polyunsaturated fatty acids (PUFAs) on colon cancer cells via their growth inhibitory metabolites and fatty acid composition changes.

BACKGROUND: Colorectal cancer is common. Polyunsaturated fatty acids (PUFAs) exert growth-inhibitory and pro-apoptotic effects on colon cancer cells. Metabolites of PUFAs such as prostaglandins (PGs), leukotrienes (LTs) and lipoxins (LXs) play a significant role in colon cancer. METHODS: Human colon cancer LoVo and RKO cells were cultured with different concentration of PUFAs and 5-fluorouracil (5-FU) in vitro. Cell morphological changes, fatty acid composition, formation of PGE2, LTB4 and LXA4 and expression of COX-2, ALOX5, PGD synthase (PGDS), microsomal prostaglandin E synthase (mPGES) were assessed in LoVo and RKO cells when supplemented with PUFAs and 5-FU. RESULTS: PUFAs and 5-FU inhibited growth of LoVo and RKO cells to the same extent at the doses used and produced significant alterations in their shape. As expected, higher concentrations of supplemented PUFAs were noted in the cells compared to control. LA, GLA, AA, ALA and EPA supplementation to LoVo cells suppressed production of PGE2, LTB4,and ALOX5, mPGES expression, but enhanced that of LXA4; whereas DHA enhanced PGE2 and LXA4 synthesis but decreased LTB4 formation and COX-2, ALOX5, mPGES expression. In contrast, 5-FU enhanced formation of PGE2, LTB4 and mPGES expression, but suppressed LXA4 synthesis and COX-2 expression. PGE2, LTB4 synthesis and ALOX5 expression was suppressed by LA, GLA, ALA and DHA; whereas AA, EPA and 5-FU enhanced PGE2 but paradoxically AA decreased and EPA and 5-FU enhanced LTB4 synthesis in RKO cells. All the PUFAs tested enhanced, while 5-FU decreased LXA4 formation in RKO cells; whereas GLA, AA, and 5-FU augmented while LA, ALA, EPA and DHA enhanced COX-2 expression in RKO cells. CONCLUSIONS: Tumoricidal action of PUFAs on colorectal LoVo and RKO cancer cells in vitro was associated with increased formation of LXA4, decreased synthesis of PGE2 and LTB4 and suppressed expression of COX-2, ALOX5, mPGES, whereas 5-FU produced contrasting actions on these indices.

A temperature induced lipocalin gene from Medicago falcata (MfTIL1) confers tolerance to cold and oxidative stress.

Temperature-induced lipocalins (TIL) are plasmalemma-localized proteins and responsive to environmental stresses. Physiological functions of MfTIL1 from Medicago sativa subsp. falcata (L.) Arcang. (hereafter falcata), a forage legume with cold and drought tolerance, were investigated in this study. MfTIL1 expression was greatly induced by 4-96 h of cold treatment, while transcript levels of the orthologs in Medicago truncatula, a model legume plant with lower cold tolerance than falcata, were reduced or not altered within 48-96 h. MfTIL1 expression was not responsive to dehydration and salinity. Compared to the wild type, transgenic tobacco plants overexpressing MfTIL1 had lower temperature (LT50) that resulted in 50 % lethal and elevated survival rate in response to freezing, elevated F v/F m and decreased ion leakage after treatments with chilling, high light and methyl viologen (MV). H2O2 and O2 (-) were less accumulated in transgenic plants than in the wild type after treatments with chilling, high light and MV, while antioxidant enzyme activities showed no difference between the two types of plants prior to or following treatments. Higher transcript levels of NtDREB3 and NtDREB4 genes were observed in transgenic plants than in the wild type under non-stressed conditions, but higher transcript levels of NtDREB1, NtDREB2, NtDREB4 and NtCOR15a genes under chilling conditions. It is suggested that MfTIL1 plays an important role in plant tolerance to cold and oxidative stress through promoted scavenging of reactive oxygen species and up-regulating expression of multiple cold responsive genes.

Protective Effects of Quercetin Against HgCl2-Induced Nephrotoxicity in Sprague-Dawley Rats.

Mercury is a well-known environmental pollutant that can cause nephropathic diseases, including acute kidney injury (AKI). Although quercetin (QC), a natural flavonoid, has been reported to have medicinal properties, its potential protective effects against mercury-induced AKI have not been evaluated. In this study, the protective effect of QC against mercury-induced AKI was investigated using biochemical parameters, new protein-based urinary biomarkers, and a histopathological approach. A 250 mg/kg dose of QC was administered orally to Sprague-Dawley male rats for 3 days before administration of mercury chloride (HgCl2). All animals were sacrificed at 24 h after HgCl2 treatment, and biomarkers associated with nephrotoxicity were measured. Our data showed that QC absolutely prevented HgCl2-induced AKI, as indicated by biochemical parameters such as blood urea nitrogen (BUN) and serum creatinine (sCr). In particular, QC markedly decreased the accumulation of Hg in the kidney. Urinary excretion of protein-based biomarkers, including clusterin, kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), monocyte chemoattractant protein-1 (MCP-1), tissue inhibitor of metalloproteinases 1 (TIMP-1), and vascular endothelial growth factor (VEGF) in response to HgCl2 administration were significantly decreased by QC pretreatment relative to that in the HgCl2-treated group. Furthermore, urinary excretion of metallothionein and Hg were significantly elevated by QC pretreatment. Histopathological examination indicated that QC protected against HgCl2-induced proximal tubular damage in the kidney. A TUNEL assay indicated that QC pretreatment significantly reduced apoptotic cell death in the kidney. The administration of QC provided significant protective effects against mercury-induced AKI.

Fingerprinting of gelatinase subtypes for different topographic regions on non-retaining placenta of Holstein cows.

The contribution of matrix metalloproteinases (MMP) to timely discharge of the placenta from bovine uterus at parturition is yet inconclusive, partly because of the presence of multiple MMP forms in situ. In the current study, the expression of different gelatinase subtypes on non-retaining placentas of Holstein cows was fingerprinted by using gelatin zymography. Different topographic regions on the placenta were measured separately, including the placentome-like structure and the fetal and maternal sides of interplacentomal placenta, all sampled from the central and peripheral areas of the placenta, respectively. The spontaneously ruptured umbilical cords were cross-sectioned as fetus end, middle and placenta end also for separate measurement. Body fluids including blood samples from the parturient cows, their neonatal calves and umbilical cord, as well as fetal fluids and the first colostrum were measured concomitantly. Results showed multiple forms of gelatinases subtypes in the placenta tissues and body fluids, including neutrophil gelatinase-associated lipocalin (NGAL)-MMP-9 complex, both the latent and active forms of MMP-2 and MMP-9; of them, the latent forms were much more abundantly and frequently expressed than the active forms. NGAL-MMP-9 complex was more prevalently present in the body fluids than in the placenta tissues. No distinguishable pattern of the expression of any gelatinase subtype was observed among the placentome-like structure, interplacentomal placenta and umbilical cord, or between fetal and maternal sides. Nonetheless, for interplacentomal placenta, proMMP-9 expression was higher in the central than in the peripheral area. In addition, proMMP-2 expression was higher in the rupture end (fetus end) than the placenta end of the umbilical cord. In conclusion, the current validated gelatin zymography detected a gradient proMMP-9 expression on the non-retaining placenta of cows in reverse to the proximity to the umbilical insertion point, and a gradient proMMP-2 expression on a section of the umbilical cord in reverse to the proximity to the rupture site, suggesting roles played by gelatinases in normal discharge of the placenta at term.

Inhibition of hematopoietic prostaglandin D2 synthase (H-PGDS) by an alkaloid extract from Combretum molle.

BACKGROUND: Hematopoietic prostaglandin D2 synthase (H-PGDS, GST Sigma) is a member of the glutathione S-transferase super family of enzymes that catalyses the conjugation of electrophilic substances with reduced glutathione. The enzyme catalyses the conversion of PGH2 to PGD2 which mediates inflammatory responses. The inhibition of H-PGDS is of importance in alleviating damage to tissues due to unwarranted synthesis of PGD2. Combretum molle has been used in African ethno medicinal practices and has been shown to reduce fever and pain. The effect of C. molle alkaloid extract on H-PGDS was thus, investigated. METHODS: H-PGDS was expressed in Escherichia coli XL1-Blue cells and purified using nickel immobilized metal affinity chromatography. The effect of C. molle alkaloid extract on H-PGDS activity was determined with 1-chloro-2, 4-dinitrobenzene (CDNB) as substrate. The effect of C. molle alkaloid extract with time on H-PGDS was determined. The mechanism of inhibition was then investigated using CDNB and glutathione (GSH) as substrates. RESULTS: A specific activity of 24 µmol/mg/min was obtained after H-PGDS had been purified. The alkaloid extract exhibited a 70% inhibition on H-PGDS with an IC50 of 13.7 µg/ml. C. molle alkaloid extract showed an uncompetitive inhibition of H-PGDS with Ki = 41 µg/ml towards GSH, and non-competitive inhibition towards CDNB with Ki = 7.7 µg/ml and Ki' = 9.2 µg/ml. CONCLUSION: The data shows that C. molle alkaloid extract is a potent inhibitor of H-PGDS. This study thus supports the traditional use of the plant for inflammation.

Regulation of mammalian siderophore 2,5-DHBA in the innate immune response to infection.

Competition for iron influences host-pathogen interactions. Pathogens secrete small iron-binding moieties, siderophores, to acquire host iron. In response, the host secretes siderophore-binding proteins, such as lipocalin 24p3, which limit siderophore-mediated iron import into bacteria. Mammals produce 2,5-dihydroxy benzoic acid, a compound that resembles a bacterial siderophore. Our data suggest that bacteria use both mammalian and bacterial siderophores. In support of this idea, supplementation with mammalian siderophore enhances bacterial growth in vitro. In addition, mice lacking the mammalian siderophore resist E. coli infection. Finally, we show that the host responds to infection by suppressing siderophore synthesis while up-regulating lipocalin 24p3 expression via TLR signaling. Thus, reciprocal regulation of 24p3 and mammalian siderophore is a protective mechanism limiting microbial access to iron.

Effects of dietary supplementation of glucosamine sulfate on intestinal inflammation in a mouse model of experimental colitis.

BACKGROUND AND AIM: Epidemiological evidences suggested an inverse association between the use of glucosamine supplements and colorectal cancer (CRC) risk. In this study, the efficacy of glucosamine to attenuate dextran sodium sulfate (DSS)-induced colitis, a precancerous condition for CRC, was evaluated. METHODS: C57BL/6 mice were separated into three groups receiving glucosamine sulfate at concentrations of 0, 0.05, and 0.10% (w/w) of AIN-93G diet, respectively for 4 weeks. Colitis was induced by supplying two cycles (5 days per cycle) of 2% DSS in the animals' drinking water. RESULTS: Glucosamine supplementation at the level of 0.10% of the diet (w/w) reduced colitis-associated symptoms as measured by disease activity index (DAI). Tumor necrosis factor-α (TNF-α), interleukin-1ß, and nuclear factor-kappa B mRNA expression in the colonic mucosa was significantly lower in animals fed 0.10% glucosamine compared with those of the control group. Expression of the tight junction proteins ZO-1 and occludin was significantly higher in the 0.10% glucosamine-supplemented group compared with the other groups. Also, colonic protein expression of lipocalin 2, and serum concentrations of interleukin-8 and amyloid P component (SAP) were significantly reduced in the 0.10% glucosamine-supplemented group compared with the control group. CONCLUSION: These results suggest that glucosamine attenuates the colitis disease activity by suppressing NF-κB activation and related inflammatory responses.

Targeting pancreatic cancer with magneto-fluorescent theranostic gold nanoshells.

AIM: We report a magneto-fluorescent theranostic nanocomplex targeted to neutrophil gelatinase-associated lipocalin (NGAL) for imaging and therapy of pancreatic cancer. MATERIALS & METHODS: Gold nanoshells resonant at 810 nm were encapsulated in silica epilayers doped with iron oxide and the near-infrared (NIR) dye indocyanine green, resulting in theranostic gold nanoshells (TGNS), which were subsequently conjugated with antibodies targeting NGAL in AsPC-1-derived xenografts in nude mice. RESULTS: Anti-NGAL-conjugated TGNS specifically targeted pancreatic cancer cells in vitro and in vivo providing contrast for both NIR fluorescence and T2-weighted MRI with higher tumor contrast than can be obtained using long-circulating, but nontargeted, PEGylated nanoparticles. The nanocomplexes also enabled highly specific cancer cell death via NIR photothermal therapy in vitro. CONCLUSION: TGNS with embedded NIR and magnetic resonance contrasts can be specifically targeted to pancreatic cancer cells with expression of early disease marker NGAL, and enable molecularly targeted imaging and photothermal therapy.

Reactive astrocytes secrete lcn2 to promote neuron death.

Glial reaction is a common feature of neurodegenerative diseases. Recent studies have suggested that reactive astrocytes gain neurotoxic properties, but exactly how reactive astrocytes contribute to neurotoxicity remains to be determined. Here, we identify lipocalin 2 (lcn2) as an inducible factor that is secreted by reactive astrocytes and that is selectively toxic to neurons. We show that lcn2 is induced in reactive astrocytes in transgenic rats with neuronal expression of mutant human TAR DNA-binding protein 43 (TDP-43) or RNA-binding protein fused in sarcoma (FUS). Therefore, lcn2 is induced in activated astrocytes in response to neurodegeneration, but its induction is independent of TDP-43 or FUS expression in astrocytes. We found that synthetic lcn2 is cytotoxic to primary neurons in a dose-dependent manner, but is innocuous to astrocytes, microglia, and oligodendrocytes. Lcn2 toxicity is increased in neurons that express a disease gene, such as mutant FUS or TDP-43. Conditioned medium from rat brain slice cultures with neuronal expression of mutant TDP-43 contains abundant lcn2 and is toxic to primary neurons as well as neurons in cultured brain slice from WT rats. Partial depletion of lcn2 by immunoprecipitation reduced conditioned medium-mediated neurotoxicity. Our data indicate that reactive astrocytes secrete lcn2, which is a potent neurotoxic mediator.

Creatine pretreatment prevents birth asphyxia-induced injury of the newborn spiny mouse kidney.

BACKGROUND: Acute kidney injury (AKI) is a major complication for infants following an asphyxic insult at birth. We aimed to determine if kidney structure and function were affected in an animal model of birth asphyxia and if maternal dietary creatine supplementation could provide an energy reserve to the fetal kidney, maintaining cellular respiration during asphyxia and preventing AKI. METHODS: Pregnant spiny mice were maintained on normal chow or chow supplemented with creatine from day 20 gestation. On day 38 (term ~39 d), pups were delivered by cesarean section (c-section) or subjected to intrauterine asphyxia. Twenty-four hours after insult, kidneys were collected for histological or molecular analysis. Urine and plasma were also collected for biochemical analysis. RESULTS: AKI was evident at 24 h after birth asphyxia, with a higher incidence of shrunken glomeruli (P < 0.02), disturbance to tubular arrangement, tubular dilatation, a twofold increase (P < 0.02) in expression of Ngal (early marker of kidney injury), and decreased expression of the podocyte differentiation marker nephrin. Maternal creatine supplementation prevented the glomerular and tubular abnormalities observed in the kidney at 24 h and the increased expression of Ngal. CONCLUSION: Maternal creatine supplementation may prove useful in ameliorating kidney injury associated with birth asphyxia.

Cloning, monoclonal antibody production, and bodily distribution pattern of a bovine lipocalin.

A bovine lipocalin, previously identified as a putative odorant-binding protein in bovine colostrum (bcOBP), was cloned and expressed, and its monoclonal antibody was established. bcOBP was constantly secreted into milk on day of parturition until at least 10 d postpartum at a concentration of 181±39 µg/L. Besides milk, bcOBP occurred in the nasal mucus, saliva, amniotic fluid, vaginal discharge, and blood plasma. Despite its low concentration, the distribution pattern and the finding that bcOBP harbored a characteristic sequence motif, CxxxC, which is conserved among insect and mammal pheromone binding proteins, suggest that bcOBP functions as a pheromone carrier. The presence of bcOBP in the plasma at varied concentrations depending on the lactation period does not exclude the possibility that bcOBP is secreted into milk from the blood. Cross-reactivity of the monoclonal antibody indicated presence of proteins homologous to bcOBP in the colostrum of farm animals of Cetartiodactyla.

[Effect of Cordyceps sinensis on the expression of HIF-1α and NGAL in rats with renal ischemia-reperfusion injury].

OBJECTIVE: To observe the level of urinary neutrophil gelatinase-associated lipocalin (NGAL), the expression of hypoxia inducible factor-1α (HIF-1α) and NGAL in rat kidney after renal ischemia and reperfusion (I/R), before and after the treatment with Cordyceps Sinensis (C. sinensis), and to explore the mechanism of C. sinensis against I/R injury. METHODS: A total of 45 healthy male Sprague-Dawley rats were randomly divided into a sham group, a renal I/R model group, and a C. sinensis group (15 in each group).The rats in the sham group and the renal I/R model group were intragastrically administered saline (2 mL/d), and rats in the treatment group were intragastricabby administered of C. sinensis [5.0 g/(kg.d)]. The rats were sacrificed at 24, 48, and 72 h, respectively after the reperfusion and urinary N-acetyl-ß-D-glucosaminidase (NAG) level was measured, renal function in rats was detected, and the pathological changes were observed with HE staining. We determined the urinary NGAL levels in the rats by ELISA, the expression of HIF-1α mRNA by RT-PCR, and the expressions of HIF-1α and NGAL proteins by confocal immunofluorescence. RESULTS: Compared with the sham group, the levels of BUN, SCr, levels of NAG and NGAL in urine were increased in the I/R group and the C. sinensis group, reached a peak at 24 h after the reperfusion and slowly declined at 48 and 72 h. Glomerular and tubulointerstitial areas in the sham group did not show any pathological change. Induced pathological changes included tubular cell necrosis, focal areas of proximal tubular dilation, distal tubular casts, effacement and loss of proximal tubule brush border, etc. Compared with the sham group, the expression of HIF-1α and NGAL in the kidney tissues of the I/R group and the C. sinensis group increased. C. sinensis can lower the level of NAG and NGAL in the urine and the expression of NGAL protein in the kidney tissues. It up-regulated the expression of HIF-1α mRNA and protein in the kidney tissues whilst attenuated the pathological changes. CONCLUSION: Renal I/R injury in rats can lead to pathological changes in renal tubular epithelial cells and renal interstitial damage, which are consistent with the pathological features of acute kidney injury (AKI).The level of urinary NAGL increases after the I/R, and positively correlates with the level of urinary NAG and pathological changes, suggesting that urinary NGAL may serve as a urinary biomarker for specific detection of tubular injury in AKI. C. sinensis can attenuate the renal I/ R-induced AKI. Its mechanism may be associated with up-regulating the expression of HIF-1α and down-regulating the expression of NGAL in the kidney tissues.