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Current time obesity is the major challenges globally and the incidence of the obesity has raised dramatically in current years. The obesity enhanced the various metabolic diseases such as diabetes, cardiac, cancer and steatohepatitis. Natural drug having the long history to ameliorate the obesity and its related metabolic disorder. In this experimental study, we scrutinized the anti-obesity effect of nimbolide against high fat diet (HFD) induced obesity in rats. Wistar rats were divided into 5 groups and each group contains 10 rats. The body weight, tissue weight was estimated at regular time. Carbohydrate, lipid, hepatic, inflammatory cytokines, antioxidant and inflammatory parameters were estimated. The mRNA expression was also estimated. Nimbolide treated groups significantly (p0.001) suppressed the body weight at dose dependent manner. Nimbolide significantly (p0.001) reduced the hepatic parameters and altered the antioxidant parameters such as thiobarbituric acid reactive substances (TBARS), glutathione (GSH), catalase (CAT), glutathione peroxidase (GPx), superoxide mutase (SOD), glutathione S transferase (GST); decreased the level of inflammatory cytokines (IL-1β, IL-6, TNF-α). Nimbolide suppressed the mRNA expression of glucose-6-phosphatase HO-1 and nuclear factor erythroid-2 related factor-2 (Nrf2). Collectively, we can say that nimbolide having the capability to suppressed the HFD induced obesity via Nrf2/HO-1 pathway.

A new species and a key to eleven species of of the genus Conophyma Zobovsky, 1898 from China is described in this paper. The new species Conophyma lini sp. nov. is similar to C. xiai Zhang et al, 2015, but differs from latter by: vertex longer, apex narrower; minimum width of interspace 1.6 times length in mesosternum; posterior margin of epiproct waved, with angular projection in the middle, furculae small and width of Epiphallus 2.5 times high. Type specimens are deposited in the Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining, Qinghai 810001, China.

It focused on the antiviral immune regulation of biofilm-localized protein kinase Dbf2p-related kinase 1 (NDR1) in viral pneumonia. Mouse alveolar monocyte RAW264.7 was used as blank control, and viral pneumonia cell model was prepared by infecting cells with respiratory syncytial virus (RSV). NDR1 overexpression vector and siRNA interference sequences were synthesized, and overexpression/silence NDR1 cell model was fabricated. About 50 ng/mL interleukin 17 (IL-17) was given to stimulate. Enzyme-linked immunosorbent assay (ELISA), quantitative reverse transcription PCR (RT-qRCR), and Western blot were performed to detect cytokines and chemokines, mRNA of inflammatory factors, and signal molecule protein expression. Notably, RSV infection increased RSV-F mRNA in RAW264.7 cells and reduced NDR1 mRNA and protein. Secretion levels of IL-6, interferon β (IFN-β), chemokine (C-X-C motif) ligand 2 (CXCL2), and chemokine (C-C motif) ligand 2 (CCL20) increased in the model group versus blank control (P 0.05). In short, NDR1 regulated innate immune response to viral pneumonia induced by IL-17, which can be used as a new target for the treatment of IL-17-induced inflammatory response and autoimmune diseases.

Objective: To explore the mechanism by which miR-129-3p affected the autophagy of interstitial cells of Cajal (ICCs) in slow transit constipation tissues through the SCF C-kit signaling pathway. Methods: Colon samples from 20 Slow transit constipation (STC) patients who underwent total colectomy plus ileorectal anastomosis or subtotal colon resection plus anti-peristaltic rectal anastomosis were collected in our hospital. The colon of 20 non-STC patients was used as control. The control of this study was 20 patients undergoing radical surgery for colon cancer (left colon cancer) in our hospital. Fifty healthy SPF Kunming mice were purchased from Liaoning Changsheng Biotechnology Co., Ltd. Results: The mRNA expression of miR-129-3p in the STC group was lower than that in the control group (CTLR) group (P

Background Autoimmune hepatitis (AIH) is a T cell-mediated immune disease that activates abnormally against hepatic antigens. We have previously reported that endometrial regenerative cells (ERCs) were a novel source of adult stem cells, which exhibiting with powerful immunomodulatory effects. Galectin-9 (Gal-9) is expressed in ERCs and plays an important role in regulating T cell response. This study aims to explore the role of ERCs in attenuation of AIH and to determine the potential mechanism of Gal-9 in ERC-mediated immune regulation. Methods ERCs were obtained from menstrual blood of healthy female volunteers. In vitro, ERCs were transfected with lentivirus vectors carrying LGALS9 gene and encoding green fluoresce protein (GFP-Gal-9-LVs) at a MOI 50, Gal-9 expression in ERCs was detected by ELISA and Q-PCR. CD4+ T cells isolated from C57BL/6 mouse spleen were co-cultured with ERCs. The proliferation of CD4+ T cells was detected by CCK-8 kit and the level of Lck/zap-70/LAT protein was measured by western blot. Furthermore, AIH was induced by ConA in C57BL/6 mice which were randomly assigned to untreated, unmodified ERC-treated and Gal-9 high-expressing ERC-treated groups. Histopathological score, liver function, CD4+/CD8+ cell infiltration in liver tissues, the proportion of immune cells in the spleen and liver, and ERC tracking were performed accordingly to assess the progression degree of AIH. Results After transfecting with GFP-Gal-9-LVs, Gal-9 expression in ERCs was significantly increased. Additionally, Gal-9 high-expressing ERCs effectively inhibited CD4+ T cell proliferation and downregulated CD4+ T cell active related proteins p-Lck/p-ZAP70/p-LAT in vitro. Furthermore, treatment with Gal-9 high-expressing ERCs restored liver function, ameliorated liver pathological damage, inhibit CD4+ and CD8+ T cell proliferation and suppress Th1 and Th17 cell response in the hepatitis mice. In addition, Gal-9 high-expressing ERCs further markedly enhanced the level of IL-10 but reduced the levels of IFN-γ, TNF-α, and IL-4 in mouse sera and liver. Cell tracking also showed that ERCs could migrate to the damaged liver organs. Conclusions The results suggested that Gal-9 was an essential modulator, which was required by ERCs in regulating T cell response and attenuating ConA-induced experimental hepatitis. And also, it provides a novel idea for the clinical treatment of AIH.

Overexpression of the antiapoptotic protein Mcl-1 provides a survival advantage to some cancer cells, making inhibition of this protein an attractive therapeutic target for the treatment of certain types of tumors. Herein, we report our efforts toward the identification of a novel series of macrocyclic Mcl-1 inhibitors featuring an α-hydroxy phenylacetic acid pharmacophore or bioisostere. This work led to the discovery of

The adenosinergic pathway represents an attractive new therapeutic approach in cancer immunotherapy. In this pathway, ecto-5-nucleotidase CD73 has the unique function of regulating production of immunosuppressive adenosine (ADO) through the hydrolysis of AMP. CD73 is overexpressed in many cancers, resulting in elevated levels of ADO that correspond to poor patient prognosis. Therefore, reducing the level of ADO via inhibition of CD73 is a potential strategy for treating cancers. Based on the binding mode of adenosine 5'-(α,β-methylene)diphosphate (AOPCP) with human CD73, we designed a series of novel monophosphonate small-molecule CD73 inhibitors. Among them, OP-5244 (35) proved to be a highly potent and orally bioavailable CD73 inhibitor. In preclinical studies, 35 completely inhibited ADO production in both human cancer cells and CD8+ T cells. Furthermore, 35 lowered the ratio of ADO/AMP significantly and reversed immunosuppression in mouse models, indicating its potential as an in vivo tool compound for further development.

In the present study, we applied our 'precise annotation' to the mitochondrial (mt) genomes of human, chimpanzee, rhesus macaque and mouse using 5' and 3' end small RNAs. Our new annotations updated previous annotations. In particular, our new annotations led to two important novel findings: (1) the identification of five Conserved Sequence Blocks (CSB1, CSB2, CSB3, LSP and HSP) in the control regions; and (2) the annotation of Transcription Initiation and novel Transcription Termination Sites. Based on these annotations, we proposed a novel model of mt transcription which can account for the mt transcription and its regulation in mammals. According to our model, Transcription Termination Sites function as switches to regulate the production of short, long primary transcripts and uninterrupted transcription, rather than simply terminate the mt transcription. Moreover, the expression levels of mitochondrial transcription termination factors control the proportions of rRNAs, mRNAs and lncRNAs in total mt RNA. Our findings point to the existence of many other, as yet unidentified, Transcription Termination Sites in mammals.

The glucocorticoid receptor (GR) has been linked to therapy resistance across a wide range of cancer types. Preclinical data suggest that antagonists of this nuclear receptor may enhance the activity of anticancer therapy. The first-generation GR antagonist mifepristone is currently undergoing clinical evaluation in various oncology settings. Structure-based modification of mifepristone led to the discovery of ORIC-101 (28), a highly potent steroidal GR antagonist with reduced androgen receptor (AR) agonistic activity amenable for dosing in androgen receptor positive tumors and with improved CYP2C8 and CYP2C9 inhibition profile to minimize drug-drug interaction potential. Unlike mifepristone, 28 could be codosed with chemotherapeutic agents readily metabolized by CYP2C8 such as paclitaxel. Furthermore, 28 demonstrated in vivo antitumor activity by enhancing response to chemotherapy in the GR+ OVCAR5 ovarian cancer xenograft model. Clinical evaluation of safety and therapeutic potential of 28 is underway.

SLC26A4 gene mutations lead to Pendred syndrome and non-syndromic hearing loss (DFNB4). The mouse model is well used to study the pathology of Pendred syndrome, however, mice with different Slc26a4 mutations exhibit different phenotypes, and these mice have severe deafness and inner ear malformations that are not imitated less severely Human phenotype. In this study, we generated a knock-in mouse model of Pendred syndrome with Slc26a4 L236P mutation to mimic the most common mutation found in human. Some L236P mice were observed to have significant vestibular dysfunction including torticollis and circling, the giant otoconia and destruction of the otoconial membrane was observed in L236P mice. Unlike other profoundly deafness in Slc26a4 mouse model, L236P mice present mild to profound hearing loss, consistent with the hearing threshold, inner ear hair cells also lost from slight to significant. Together, these data demonstrate that the L236P mouse phenotype is more similar to the human phenotype and should be used as a tool for further research into the human Pendred syndrome.

Cdc14a is an evolutionarily conserved dual-specific protein phosphatase, and it plays different roles in different organisms. Cdc14a mutations in human have been reported to cause male infertility, while the specific role of Cdc14a in regulation of the male reproductive system remains elusive. In the present study, we established a knockout mouse model to study the function of Cdc14a in male reproductive system. Cdc14a-/- male mice were subfertile and they could only produce very few offspring. The number of sperm was decreased, the sperm motility was impaired, and the proportion of sperm with abnormal morphology was elevated in Cdc14a-/- mice. When we mated Cdc14a-/- male mice with wild-type (WT) female mice, fertilized eggs could be found in female fallopian tubes, however, the majority of these embryos died during development. Some empty spaces were observed in seminiferous tubule of Cdc14a-/- testes. Compared with WT male mice, the proportions of pachytene spermatocytes were increased and germ cells stained with γH2ax were decreased in Cdc14a-/- male mice, indicating that knockout of Cdc14a inhibited meiotic initiation. Subsequently, we analyzed the expression levels of some substrate proteins of Cdc14a, including Cdc25a, Wee1, and PR-Set7, and compared those with WT testes, in which the expression levels of these proteins were significantly increased in Cdc14a-/- testes. Our results revealed that Cdc14a-/- male mice are highly subfertile, and Cdc14a is essential for normal spermatogenesis and sperm function.

1. AMG 232 is a novel inhibitor of the p53-MDM2 protein-protein interaction currently in Phase I clinical trials for multiple tumor indications. The objectives of the investigations reported in this article were to characterize the pharmacokinetic and drug metabolism properties of AMG 232 in pre-clinical species in vivo and in vitro, and in humans in vitro, and to predict its pharmacokinetics in humans through integrating PKDM data. 2. AMG 232 exhibited low clearance (0.25 × Qh) and moderate to high oral bioavailability in mice, rats and monkeys (42%), but high clearance (0.74 × Qh) and low oral exposure in dogs (18%). 3. Biotransformation was the major route of elimination of AMG 232 in rats, with only 7% of intravenously administered (14)C-labeled AMG 232 recovered as parent molecule in bile. The major metabolite was an acyl glucuronide as measured by in vivo rat studies and in vitro hepatocyte incubations in multiple species. 4. The in vitro-in vivo correlation of AMG 232 clearance was within 2-fold in pre-clinical species using hepatocytes. AMG 232 was predicted to exhibit low clearance, high volume distribution and long half-life in humans. The predictions are consistent with the preliminary human pharmacokinetic parameters of AMG 232 in clinical trials.

Structure-based rational design and extensive structure-activity relationship studies led to the discovery of AMG 232 (1), a potent piperidinone inhibitor of the MDM2-p53 association, which is currently being evaluated in human clinical trials for the treatment of cancer. Further modifications of 1, including replacing the carboxylic acid with a 4-amidobenzoic acid, afforded AM-7209 (25), featuring improved potency (KD from ITC competition was 38 pM, SJSA-1 EdU IC50 = 1.6 nM), remarkable pharmacokinetic properties, and in vivo antitumor activity in both the SJSA-1 osteosarcoma xenograft model (ED50 = 2.6 mg/kg QD) and the HCT-116 colorectal carcinoma xenograft model (ED50 = 10 mg/kg QD). In addition, 25 possesses distinct mechanisms of elimination compared to 1.

We recently reported on the discovery of AMG 232, a potent and selective piperidinone inhibitor of the MDM2-p53 interaction. AMG 232 is being evaluated in human clinical trials for cancer. Continued exploration of the N-alkyl substituent of this series, in an effort to optimize interactions with the MDM2 glycine-58 shelf region, led to the discovery of sulfonamides such as compounds 31 and 38 that have similar potency, hepatocyte stability and rat pharmacokinetic properties to AMG 232.

We previously reported the discovery of AMG 232, a highly potent and selective piperidinone inhibitor of the MDM2-p53 interaction. Our continued search for potent and diverse analogues led to the discovery of novel morpholinone MDM2 inhibitors. This change to a morpholinone core has a significant impact on both potency and metabolic stability compared to the piperidinone series. Within this morpholinone series, AM-8735 emerged as an inhibitor with remarkable biochemical potency (HTRF IC50 = 0.4 nM) and cellular potency (SJSA-1 EdU IC50 = 25 nM), as well as pharmacokinetic properties. Compound 4 also shows excellent antitumor activity in the SJSA-1 osteosarcoma xenograft model with an ED50 of 41 mg/kg. Lead optimization toward the discovery of this inhibitor as well as key differences between the morpholinone and the piperidinone series will be described herein.

Aims Catalase catalyzes the degradation of H2O2. Acinetobacter species have four predicted catalase genes, katA, katE, katG, and katX. The aims of the present study seek to determine which catalase(s) plays a predominant role in determining the resistance to H2O2, and to assess the role of catalase in Acinetobacter virulence. Main methods Mutants of Acinetobacter baumannii and Acinetobacter nosocomialis with deficiencies in katA, katE, katG, and katX were tested for sensitivity to H2O2, either by halo assays or by liquid culture assays. Respiratory burst of neutrophils, in response to A. nosocomialis, was assessed by chemiluminescence to examine the effects of catalase on the production of reactive oxygen species (ROS) in neutrophils. Bacterial virulence was assessed using a Galleria mellonella larva infection model. Key findings The capacities of A. baumannii and A. nosocomialis to degrade H2O2 are largely dependent on katE. The resistance of both A. baumannii and A. nosocomialis to H2O2 is primarily determined by the katG gene, although katE also plays a minor role in H2O2 resistance. Bacteria lacking both the katG and katE genes exhibit the highest sensitivity to H2O2. While A. nosocomialis bacteria with katE and/or katG were able to decrease ROS production by neutrophils, these cells also induced a more robust respiratory burst in neutrophils than did cells deficient in both katE and katG. We also found that A. nosocomialis deficient in both katE and katG was more virulent than the wildtype A. nosocomialis strain. Significance Our findings suggest that inhibition of Acinetobacter catalase may help to overcome the resistance of Acinetobacter species to microbicidal H2O2 and facilitate bacterial disinfection.

The synthesis and SAR of a series of 4,4-disubstituted cyclohexylbenzamide inhibitors of 11β-HSD1 are described. Optimization rapidly led to potent, highly selective, and orally bioavailable inhibitors demonstrating efficacy in both rat and non-human primate ex vivo pharmacodynamic models.

We report the discovery of potent benzamide inhibitors of 11beta-hydroxysteroid dehydrogenase (11beta-HSD1). The optimization and correlation of in vitro and in vivo metabolic stability will be described. Through modifications to our initial lead 2, we discovered pyridyl compound 13. This compound has a favorable pharmacokinetic profile across three species and showed a dose-dependent decrease in adipose 11beta-HSD1 activity in a monkey ex vivo pharmacodynamic model.

High-throughput screening of a small-molecule compound library resulted in the identification of a series of arylsulfonylpiperazines that are potent and selective inhibitors of human 11β-Hydroxysteroid Dehydrogenase Type 1 (11β-HSD1). Optimization of the initial lead resulted in the discovery of compound (R)-45 (11β-HSD1 IC50 = 3 nM).

In this Letter, we report the continued optimization of the N-acyl-2-aminobenzimidazole series, focusing in particular on the N-alkyl substituent and 5-position of the benzimidazole based on the binding mode and the early SAR. These efforts led to the discovery of 16, a highly potent, selective, and orally bioavailable inhibitor of IRAK-4.

Bone morphogenetic proteins (BMPs) belong to the transforming growth factor superfamily and have been implicated in chondrogenesis and neuronal differentiation. In order to examine the function of bone morphogenetic protein 2 (BMP‑2) on the differentiation of nitrergic enteric neurons in slow transit constipation (STC), the expression of BMP‑2 and neuronal nitric oxide synthase (nNOS) was investigated in the myenteric nerve plexus in STC and control tissues by immunohistochemical assays. The present study demonstrated that BMP‑2 and nNOS were expressed in the myenteric nerve plexus and their levels were differentially altered in the STC group and control group. In addition, the effect of BMP‑2 on primary myenteric neurons was investigated by measuring the neurite length. The results demonstrated that BMP‑2 regulated the differentiation of primary enteric neurons and increased the length of neurites compared with the control group. In addition, the effect of BMP‑2 on the expression of nNOS was also investigated in primary enteric neurons and the Smad1 signal transduction pathway by western blot analysis, reverse transcription quantitative polymerase chain reaction and immunofluorescence assay. The results suggested that BMP‑2 promoted the expression of nNOS in primary myenteric neurons and induced phosphorylation of Smad1. These data indicate a new role for BMP‑2 as an important transcriptional cofactor that regulates the differentiation of nitrergic enteric neurons through the Smad1 pathway. Intervention of BMP‑2 may be useful for the treatment of STC.

We previously reported the discovery of potent and selective morpholinone and piperidinone inhibitors of the MDM2-p53 interaction. These inhibitors have in common a carboxylic acid moiety that engages in an electrostatic interaction with MDM2-His96. Our continued search for potent and diverse inhibitors led to the discovery of novel replacements for these acids uncovering new interactions with the MDM2 protein. In particular, using pyridine or thiazole as isosteres of the carboxylic acid moiety resulted in very potent analogues. From these, AM-6761 (4) emerged as a potent inhibitor with remarkable biochemical (HTRF IC50 = 0.1 nM) and cellular potency (SJSA-1 EdU IC50 = 16 nM), as well as favorable pharmacokinetic properties. Compound 4 also shows excellent antitumor activity in the SJSA-1 osteosarcoma xenograft model with an ED50 of 11 mg/kg. Optimization efforts toward the discovery of these inhibitors as well as the new interactions observed with the MDM2 protein are described herein.

To observe the effect of intestinal microflora imbalance caused by antibiotics on the maturity of dendritic cells (DCs) and the expressions of Toll-like receptor 2 (TLR2), TLR4 on DCs in the lung of ovalbumin (OVA)-induced asthma mice.Sixty-four 3-week-old female BALB/c mice were divided randomly into 4 groups, i.e. microbiota imbalance group, microbiota imbalamce combined with OVA challenge group, OVA challenge group and control group, with sixteen mice in each group. On day 14, flow cytometry was adopted to measure the DC subtypes and maturity (MHC-II molecules), and the expressions of TLR2, TLR4 on DCs. The expressions of transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6) in situ in lung were detected by immunohistochemical staining. The levels of TGF-β1 and IL-6 in bronchoalveolar lavage fluid (BALF) were examined by ELISA.Compared with control group and OVA challenge group, MHC-II molecules and TLR2, TLR4 expressions on DCs in the lung increased in both microbiota imbalance combined with OVA challenge group and microbiota imbalance group, but they were not significantly different between the two groups (P0.05). Compared with the other three groups, microbiota imbalance combined with OVA challenge group showed the up-regulated expressions of TGF-β1 and IL-6 proteins in lung and BALF.The alterations in intestinal microflora balance promoted the maturity of DCs and raised the expressions of TLR2 and TLR4 on DCs in mouse lung.

Structural analysis of both the MDM2-p53 protein-protein interaction and several small molecules bound to MDM2 led to the design and synthesis of tetrasubstituted morpholinone 10, an MDM2 inhibitor with a biochemical IC50 of 1.0 μM. The cocrystal structure of 10 with MDM2 inspired two independent optimization strategies and resulted in the discovery of morpholinones 16 and 27 possessing distinct binding modes. Both analogues were potent MDM2 inhibitors in biochemical and cellular assays, and morpholinone 27 (IC50 = 0.10 μM) also displayed suitable PK profile for in vivo animal experiments. A pharmacodynamic (PD) experiment in mice implanted with human SJSA-1 tumors showed p21(WAF1) mRNA induction (2.7-fold over vehicle) upon oral dosing of 27 at 300 mg/kg.

Structure-based rational design led to the discovery of novel inhibitors of the MDM2–p53 protein–protein interaction. The affinity of these compounds for MDM2 was improved through conformational control of both the piperidinone ring and the appended N-alkyl substituent. Optimization afforded 29 (AM-8553), a potent and selective MDM2 inhibitor with excellent pharmacokinetic properties and in vivo efficacy.

In this communication, human 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitory activities of a novel series of diarylsulfones are described. Optimization of this series resulted in several highly potent 11β-HSD1 inhibitors with excellent pharmacokinetic (PK) properties. Compound (S)-25 showed excellent efficacy in a non-human primate ex vivo pharmacodynamic model.

Novel 4,4-disubstituted cyclohexylbenzamide inhibitors of 11beta-HSD1 were optimized to account for liabilities relating to in vitro pharmacokinetics, cytotoxicity and protein-related shifts in potency. A representative compound showing favorable in vivo pharmacokinetics was found to be an efficacious inhibitor of 11beta-HSD1 in a rat pharmacodynamic model (ED(50)=10mg/kg).

The synthesis and SAR of a series of arylsulfonylpiperazine inhibitors of 11beta-HSD1 are described. Optimization rapidly led to potent, selective, and orally bioavailable inhibitors demonstrating efficacy in a cynomolgus monkey ex vivo enzyme inhibition model.

Adenosine is a determinant of metabolic control of organ function increasing oxygen supply through the A2 class of adenosine receptors and reducing oxygen demand through A1 adenosine receptors (A1AR). In the kidney, activation of A1AR in afferent glomerular arterioles has been suggested to contribute to tubuloglomerular feedback (TGF), the vasoconstriction elicited by elevations in [NaCl] in the macula densa region of the nephron. To further elucidate the role of A1AR in TGF, we have generated mice in which the entire A1AR coding sequence was deleted by homologous recombination. Homozygous A1AR mutants that do not express A1AR mRNA transcripts and do not respond to A1AR agonists are viable and without gross anatomical abnormalities. Plasma and urinary electrolytes were not different between genotypes. Likewise, arterial blood pressure, heart rates, and glomerular filtration rates were indistinguishable between A1AR +/+ , A1AR +/− , and A1AR −/− mice. TGF responses to an increase in loop of Henle flow rate from 0 to 30 nl/min, whether determined as change of stop flow pressure or early proximal flow rate, were completely abolished in A1AR −/− mice (stop flow pressure response, −6.8 ± 0.55 mmHg and −0.4 ± 0.2 in A1AR +/+ and A1AR −/− mice; early proximal flow rate response, −3.4 ± 0.4 nl/min and +0.02 ± 0.3 nl/min in A1AR +/+ and A1AR −/− mice). Absence of TGF responses in A1AR-deficient mice suggests that adenosine is a required constituent of the juxtaglomerular signaling pathway. A1AR null mutant mice are a promising tool to study the functional role of A1AR in different target tissues.

Induction of the inducible cyclooxygenase isoform COX-2 is likely to be an important mechanism for increased prostaglandin production in renal inflammation. We examined the effect of lipopolysaccharide (LPS) on regional renal COX-2 expression in the rat. In the inner medulla, LPS injection (4 mg/kg ip) induced a twofold and 2.5-fold increase in the levels of COX-2 mRNA and COX-2 protein, respectively. In contrast, COX-2 expression in the renal cortex was not significantly altered. COX-2 promoter transgenic mice were created using the 2.7-kb flanking region of the rat COX-2 gene. In these animals, LPS injection induced reporter gene expression predominately in the inner medulla. The LPS receptor CD14, usually regarded as a monocyte/macrophage-specific marker, was found to be abundantly expressed in the inner medulla and in dissected inner medullary collecting duct (IMCD) cells, suggesting that it may mediate medullary COX-2 induction. CD14 was present only at low levels in cortex and cortical segments, including glomeruli. In cultured cells, it was abundant in mouse IMCD (mIMCD-K2) cells and renal medullary interstitial cells, but largely undetectable in mesangial cells and M1 cells, a cell line derived from mouse cortical collecting ducts. In the mIMCD-K2 cell line, LPS significantly induced COX-2 mRNA expression, with concomitant induction of CD14. LPS-stimulated COX-2 expression was reduced by the addition of an anti-CD14 monoclonal antibody to the culture medium. These results demonstrate that LPS selectively stimulates COX-2 expression in the renal inner medulla through a CD14-dependent mechanism.