Vibrio vulnificus causes fatal infections in susceptible individuals. Group 1 capsular polysaccharide (CPS) operon is responsible for CPS expression, which plays an essential role in the pathogenesis of this pathogen. Cyclic AMP (cAMP) and cAMP receptor protein (crp) complex, which responds to glucose availability and functions as a global regulator, has been known to affect CPS production in this pathogen. This study was undertaken to experimentally verify whether cAMP-Crp directly or indirectly affects CPS production. A mutation in cyaA encoding adenylate cyclase, which is required for cAMP biosynthesis, inhibited V. vulnificus growth and changed opaque colonies to translucent colonies, and these changes were recovered by complementing cyaA or by adding exogenous cAMP. A mutation in crp encoding Crp also inhibited V. vulnificus growth and changed opaque colonies to translucent colonies, and these changes were recovered by complementing crp. Moreover, the crp or cyaA mutation decreased the susceptibility of V. vulnificus against NaOCl. The crp mutation reduced the transcription levels of group 1 CPS operon on a per cell basis. Glucose addition in the absence of Crp stimulated V. vulnificus growth, changed translucent colonies to opaque colonies, and increased the transcription levels of group 1 CPS operon. These results indicate that cAMP or Crp is indirectly involved in optimal CPS production by positively affecting metabolism or V. vulnificus growth rather than by directly controlling the expression of group 1 CPS operon.
Adenylyl Cyclases ; Complement System Proteins ; Cyclic AMP Receptor Protein ; Cyclic AMP* ; Glucose ; Metabolism ; Operon ; Vibrio vulnificus

OBJECTIVETo explore the relationship of aging with the changes of endogenous carbon monoxide (CO), cGMP and cAMP contents in the penile tissues of rats.

METHODSTwenty-four male rats were equally divided into an 8-month, a 16-month and a 24-month group, and their penile erection was detected by injecting apomorphine, their penile cavernous body harvested, and the contents of CO, cAPM and cGMP detected by improved dual wavelength spectrophotometry.

RESULTSThe contents of CO, cAPM and cGMP were reduced with the increase of age, with statistically significant differences between the three age groups (P < 0.01).

CONCLUSIONAging significantly decreased the contents of CO, cAMP and cGMP in the penile tissues of the rats, which suggests that aging might play an important role in erectile dysfunction.

Aging ; physiology ; Animals ; Carbon Monoxide ; metabolism ; Cyclic AMP ; metabolism ; Cyclic GMP ; metabolism ; Male ; Penis ; metabolism ; Rats ; Rats, Wistar

Taurochenodeoxycholic acid (TCDCA) is one of the main effective components of bile acid, playing critical roles in apoptosis and immune responses through the TGR5 receptor. In this study, we reveal the interaction between TCDCA and TGR5 receptor in TGR5-knockdown H1299 cells and the regulation of inflammation via the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA)-cAMP response element binding (CREB) signal pathway in NR8383 macrophages. In TGR5-knockdown H1299 cells, TCDCA significantly activated cAMP level via TGR5 receptor, indicating TCDCA can bind to TGR5; in NR8383 macrophages TCDCA increased cAMP content compared to treatment with the adenylate cyclase (AC) inhibitor SQ22536. Moreover, activated cAMP can significantly enhance gene expression and protein levels of its downstream proteins PKA and CREB compared with groups of inhibitors. Additionally, TCDCA decreased tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-8 and IL-12 through nuclear factor kappa light chain enhancer of activated B cells (NF-κB) activity. PKA and CREB are primary regulators of anti-inflammatory and immune response. Our results thus demonstrate TCDCA plays an essential anti-inflammatory role via the signaling pathway of cAMP-PKA-CREB induced by TGR5 receptor.
Animals ; Cell Line ; Cyclic AMP/metabolism* ; Cyclic AMP Response Element-Binding Protein/metabolism* ; Cyclic AMP-Dependent Protein Kinases/metabolism* ; Cytokines/metabolism* ; Humans ; Inflammation ; Macrophages ; Rats ; Receptors, G-Protein-Coupled/metabolism* ; Signal Transduction/drug effects* ; Taurochenodeoxycholic Acid/pharmacology*

Animals ; Cyclic AMP ; metabolism ; Cyclic GMP ; metabolism ; Male ; Myocytes, Cardiac ; metabolism ; Physical Conditioning, Animal ; Rats ; Rats, Sprague-Dawley ; Swimming

OBJECTIVE: To observe the direct intervention effects of electroacupuncture (EA) and non-steroid anti-inflammatory drugs (NSAIDs) on pain memory, and to explore their effects on cAMP/PKA/cAMP pathway in anterior cingulate gyrus (ACC). METHODS: Fifty clean healthy male SD rats were randomly divided into a control group, a model group, an indomethacin group, an EA group and a sham EA group, 10 rats in each group. Except the control group, the pain memory model was established in the remaining four groups by twice injection of carrageenan at foot; 0.1 mL of 2%λ-carrageenan was subcutaneously injected at the left foot of rats; 14 days later, when the pain threshold of rats of each group returned to the basic level, the second injection was performed with the same procedure. The rats in the EA group were treated with EA at bilateral "Zusanli" (ST 36) for 30 min; the rats in the indomethacin group was treated with indomethacin intragastric administration with the dose of 3 mg/kg; the rats in the sham EA group was treated with EA without electricity at the point 0.3 mm forward "Zusanli" (ST 36) with the depth of 2 mm for 30 min; the rats in the control group was not given any invention. All the above interventions were performed 5 h, 1 d, 2 d and 3 d after the second injection of 2% λ-carrageenan. The left-side paw withdrawal thresholds (PWT) were observed before the first injection, 4 h, 3 d, 5 d after the first injection, before the second injection and 4 h, 1 d, 2 d, 3 d after the second injection. Three days after the second injection, the number of positive cells of cAMP, p-PKA, p-CREB and the number of positive cells of protein co-expression in the right ACC brain area were detected by immunofluorescence, and the relative protein expression of p-PKA and p-CREB were detected by Western blot. RESULTS: Compared with the control group, the PWTs in the model group decreased significantly 4 h, 3 d and 5 d after the first injection and 1 d, 2 d and 3 d after the second injection (<0.05); compared with the control group, the positive expression of cAMP, p-PKA and p-CREB in the right ACC brain area in the model group increased significantly (<0.05), and the number of positive cells of the co-expression of cAMP/p-PKA and p-PKA/p-CREB also increased significantly (<0.05). Compared with the model group, indomethacin group and sham EA group, the PWTs in the EA group were increased significantly 1 d, 2 d and 3 d after the second injection (<0.05); compared with the model group, indomethacin group and sham EA group, the positive expression of p-PKA and p-CREB in the right ACC brain area in the EA group decreased significantly (<0.05), and the number of positive cells of co-expression of cAMP/p-PKA and p-PKA/p-CREB was decreased significantly (<0.05). Compared with the model group and sham EA group, the positive expression of cAMP in the right ACC brain area was decreased in the EA group (<0.05). CONCLUSION EA have a direct intervention effect on pain memory, which have significant advantage over NSAIDs in the treatment of chronic pain. The advantage effect of EA on pain memory may be related to the inhibition of cAMP/PKA/CREB pathway in ACC area.
Animals ; Anti-Inflammatory Agents, Non-Steroidal ; therapeutic use ; Cyclic AMP ; metabolism ; Cyclic AMP Response Element-Binding Protein ; metabolism ; Cyclic AMP-Dependent Protein Kinases ; metabolism ; Electroacupuncture ; Gyrus Cinguli ; metabolism ; Male ; Pain Threshold ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Signal Transduction

In order to investigate the correlation between traumatic servity and blood cAMP and cGMP levels in the patients with acute trauma and its clinical significance, 120 cases of trauma were randomly selected and divided into 4 groups (n = 30 in each group): mildly traumatic group (ISS < or = 9), moderately traumatic group (ISS = 10-16), severely traumatic group (ISS = 17-25) and dangerously traumatic group (> 25). The cAMP and cGMP levels were assayed in sera, leucocytes and platelets respectively in 6 h and 24 h after trauma. The results showed that cAMP and cGMP levels were elevated significantly in sera and platelets (P < 0.05 or P < 0.01), meanwhile cGMP levels in leucocytes (P < 0.05). It was concluded that cAMP and cGMP might play an important role in traumatic stress, participate in the cellular signal transducation and promote the immune function of leucocytes and the coagulation founction of platelets. Serum cAMP and cGMP levels were upregulated correspondingly as ISS increased, and positively correlated to the traumatic severity.
Blood Platelets/metabolism ; Cyclic AMP/*blood ; Cyclic GMP/*blood ; *Injury Severity Score ; Leukocytes/metabolism ; Wounds and Injuries/*blood

OBJECTIVETo review the role of cyclic adenosine monophosphate (cAMP) signal pathway in the pathogenesis of lymphoma and explore a potential lymphoma therapy targeted on this signaling pathway.

DATA SOURCESThe data cited in this review were mainly obtained from the articles listed in Medline and PubMed, published from January 1995 to June 2009. The search terms were "cAMP" and "lymphoma".

STUDY SELECTIONArticles regarding the role of the cAMP pathway in apoptosis of lymphoma and associated cells and its potential role in targeted therapy of lymphoma.

RESULTSIn the transformation of lymphocytic malignancies, several signal pathways are involved. Among of them, the cAMP pathway has attracted increasing attention because of its apoptosis-inducing role in several lymphoma cells. cAMP pathway impairment is found to influence the prognosis of lymphoma. Targeted therapy to the cAMP pathway seems to be a new direction for lymphoma treatment, aiming at restoring the cAMP function.

CONCLUSIONScAMP signal pathway has different effects on various lymphoma cells. cAMP analogues and phosphodiesterase 4B (PDE4B) inhibitors have potential clinical significance. However, many challenges remain in understanding the various roles of such agents.

Animals ; Cyclic AMP ; metabolism ; Humans ; Lymphoma ; metabolism ; Models, Biological ; Signal Transduction ; physiology

OBJECTIVETo test whether Porphyromonas gingivalis (P. gingivalis) could produce bacterial signal molecule, bis-(3'-5')-cyclic dimeric adenosine monophosphate (c-di-AMP) and lay the foundation for explorations of its roles in life metabolism and periodontitis immunity of P. gingivalis.

METHODSP. gingivalis standard strain ATCC33277 was used as the experimental strain to extract nucleic acids from the bacteria. Then, c-di-AMP was detected using high performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS). Subsequently, HPLC was used to validate the sample further.

RESULTSBased on the signal/noise (S/N) for 3 : 1, the limit of determination of HPLC-MS/MS for peak time of c-di-AMP standard substances was 7.49 min and nucleic acid extractions from P. gingivalis was 8.82 min (S/N > 3). Further confirmation of HPLC showed that nucleic acid extractions from both P. gingivalis and c-di-AMP standard substances pre- sented goal absorbent peaks at 15.7 min, with the same ultraviolet absorbent spectrum.

CONCLUSIONThe nucleic acid extrac- tions from P. gingivalis contained c-di-AMP, which shows that P. gingivalis could produce c-di-AMP.

Chromatography, High Pressure Liquid ; Cyclic AMP ; chemistry ; metabolism ; Periodontitis ; Porphyromonas gingivalis ; metabolism ; Tandem Mass Spectrometry

OBJECTIVEThe complex of the cyclic AMP receptor protein (CRP) and cAMP is an important transcriptional regulator of numerous genes in prokaryotes. The transport of mannitol through the phosphotransferase systems (PTS) is regulated by the CRP-cAMP complex. The aim of the study is to investigate how the CRP-cAMP complex acting on the mannitol PTS operon mtl of the Vibrio cholerae El Tor biotype.

METHODSThe crp mutant strain was generated by homologous recombination to assess the need of CRP to activate the mannitol PTS operon of V. cholerae El Tor. Electrophoretic mobility shift assays (EMSA) and the reporter plasmid pBBRlux were used to confirm the role that the CRP-cAMP complex playing on the mannitol PTS operon mtl.

RESULTSIn this study, we confirmed that CRP is strictly needed for the activation of the mtl operon. We further experimentally identified five CRP binding sites within the promoter region upstream of the mannitol PTS operon mtl of the Vibrio cholerae El Tor biotype and found that these sites display different affinities for CRP and provide different contributions to the activation of the operon.

CONCLUSIONThe five binding sites collectively confer the strong activation of mannitol transfer by CRP in V. cholerae, indicating an elaborate and subtle CRP activation mechanism.

Bacterial Proteins ; genetics ; Base Sequence ; Cyclic AMP ; metabolism ; Cyclic AMP Receptor Protein ; Gene Expression Regulation, Bacterial ; Mannitol ; Molecular Sequence Data ; Operon ; Phosphotransferases ; Vibrio cholerae

We found previously that ACh can significantly inhibit the proliferation of cultured human pituitary adenoma cells. In order to make a further investigation of the mechanism of the inhibitory effect of ACh on the proliferation of pituitary adenoma cells, we observed the levels of protein kinase C (PKC), [Ca(2+)](i) and cAMP/cGMP in cultured pituitary adenoma cells after treatment with ACh. The results demonstrate that (1) compared with control, PMA, a PKC activator, increased the activity of cytoplasm, membrane and total PKC in human pituitary adenoma cells. However, after a 15-min treatment with ACh (10 micromol/L), a significant reduction of the activity of cytoplasm, membrane and total PKC in human pituitary adenoma cells was observed, and the reduction effect could be blocked by atropine. (2) The level of [Ca(2+)](i) of single adenoma cells was found to decrease immediately on the addition of ACh (10 micromol/L), which could also be blocked by atropine. (3) ACh increased the amount of cAMP in the cytoplasm of human pituitary adenoma cells, but had no effect on that of cGMP. These data provide an important clue to explore the molecular mechanisms of the inhibitory effect of ACh on the proliferation of pituitary adenoma cells, and suggest that the modulating effect of ACh on the proliferation of pituitary adenoma cells results from the interactions of several cellular signaling pathways.
Acetylcholine ; physiology ; Adenoma ; metabolism ; pathology ; Calcium ; metabolism ; Cyclic AMP ; metabolism ; Cyclic GMP ; metabolism ; Humans ; Pituitary Neoplasms ; metabolism ; pathology ; Protein Kinase C ; metabolism ; Signal Transduction ; physiology ; Tumor Cells, Cultured