Cyclic Stretch Promotes Proliferation and Contraction of Human Bladder Smooth Muscle Cells by Cajal-Mediated c-kit Expression in Interstitial Cells.

The present study was performed to assess the effect of mechanical stretch on the proliferation and contractile function of hBSMCs. MATERIAL AND METHODS hBSMCs and ICCs were seeded at 8×104 cells/well in 6-well silicone elastomer-bottomed culture plates coated with type I collagen, and grown to 80% confluence in DMEM/10% FBS and a 5% CO₂ humidified atmosphere at 37°C. Cells of hBSMCs and hBSMCs/ICCs of co-culture were then subjected to continuous cycles of stretch-relaxation using a computer-driven, stretch-inducing device. The treated concentration of imatinib was 10 μM. Mechanisms underlying observed hBSMCs contraction were examined using Western blotting and RT-PCR. The 0.1 μM carbachol was separately added to the experimental groups, and 300 s was recorded by laser scanning confocal microscope. RESULTS
We found that mechanical stretch increased contraction and proliferation of hBSMCs. Calcium ion activity increased significantly after mechanical stretch. The number of hBSMCs was significantly increased after the combination mechanical stretch with ICCs treatment. After combination mechanical stretch with hBSMCs/ICCs treatment, the mRNA and protein level of M2, M3, and c-kit were significantly increased. After combination of mechanical stretch with no imatinib treatment, the proliferation of hBSMCs was higher than others, and the mRNA and protein level of M2 and M3 were significantly increased.
We revealed that ICCs could promote hBSMC proliferation and contraction, and cyclic stretch could promote acetylcholine receptor M2 and M3 caused by c-kit in the ICCs, which promoted the contraction of hBSMCs.

177Lu Labeled Cyclic Minigastrin Analogues with Therapeutic Activity in CCK2R Expressing Tumors: Preclinical Evaluation of a Kit Formulation.

Minigastrin (MG) analogues specifically target cholecystokinin-2 receptors (CCK2R) expressed in different tumors and enable targeted radiotherapy of advanced and disseminated disease when radiolabeled with a beta emitter such as 177Lu. Especially truncated MG analogues missing the penta-Glu sequence are associated with low kidney retention and seem therefore most promising for therapeutic use. Based on [d-Glu1,desGlu2-6]MG (MG11) we have designed the two cyclic MG analogues cyclo1,9[γ-d-Glu1,desGlu2-6,d-Lys9]MG (cyclo-MG1) and cyclo1,9[γ-d-Glu1,desGlu2-6,d-Lys9,Nle11]MG (cyclo-MG2). In the present work we have developed and preclinically evaluated a pharmaceutical kit formulation for the labeling with 177Lu of the two DOTA-conjugated cyclic MG analogues. The stability of the kits during storage as well as the stability of the radiolabeled peptides was investigated. A cell line stably transfected with human CCK2R and a control cell line without receptor expression were used for in vitro and in vivo studies with the radioligands prepared from kit formulations. In terms of stability 177Lu-DOTA-cyclo-MG2 showed advantages over 177Lu-DOTA-cyclo-MG1. Still, for both radioligands a high receptor-mediated cell uptake and favorable pharmacokinetic profile combining receptor-specific tumor uptake with low unspecific tissue uptake and low kidney retention were confirmed.
Investigating the therapy efficacy and treatment toxicity in xenografted BALB/c nude mice a receptor-specific and comparable therapeutic effect could be demonstrated for both radioligands. A 1.7- to 2.6-fold increase in tumor volume doubling time was observed for receptor-positive tumors in treated versus untreated animals, which was 39-73% higher when compared to receptor-negative tumors. The treatment was connected with transient bone marrow toxicity and minor signs of kidney toxicity. All together the obtained results support further studies for the clinical translation of this new therapeutic approach.

Differential regulation of kit ligand A (kitlga) expression in the zebrafish ovarian follicle cells–evidence for the existence of a cyclic adenosine 3′, 5′ monophosphate-mediated binary regulatory system during folliculogenesis.

  • Kit ligand (Kitl) is an important paracrine factor involved in the activation of primordial follicles from the quiescent pool and in the maintenance of meiotic arrest before germinal vesicle breakdown (GVBD). It has been reported that follicle-stimulating hormone (FSH) stimulates but luteinizing hormone (LH) suppresses the expression of Kitl in the granulosa cells in mammals. Considering that both gonadotropins signal in the follicle cells mainly by activating cyclic adenosine 3′, 5′-monophosphate (cAMP) pathway, we are intrigued by how cAMP differentially regulates Kitl expression. In the present study, we demonstrated that both human chorionic gonadotropin (hCG) and pituitary adenylate cyclase activating polypeptide (PACAP) inhibited insulin-like growth factor I (IGF-I)-induced Akt phosphorylation and kitlga expression in the zebrafish follicle cells. Further experiments showed that cAMP was involved in regulating the expression of kitlga.
  • However, two cAMP-activated effectors, protein kinase A (PKA) and exchange protein directly activated by cAMP (Epac), had converse effects. PKA promoted whereas Epac inhibited the expression of kitlga, as demonstrated by the respective activators. Interestingly, cAMP also appeared to exert differential effects on kitlga expression at different stages of follicle development during folliculogenesis, significantly stimulating kitlga expression at the early growth stage but suppressing it at the full-grown stage before final oocyte maturation, implying a potential mechanism for differential effects of the same pathway at different stages.
  • The inhibitory effect of forskolin (activator of adenylate cyclase) and H89 (inhibitor of PKA) on IGF-I-induced expression of kitlga suggested cross-talk between the cAMP and IGF-I-activated PI3K-Akt pathways. This study, together with our previous findings on IGF-I regulation of kitlga expression, provides important clues to the underlying mechanism that regulates Kit ligand expression during folliculogenesis in the ovary.

Cyclic AMP

HY-B1511 MedChemExpress 500mg 142.8 EUR

Cyclic somatostatin

HY-P0084 MedChemExpress 50mg 308.4 EUR

Cyclic AMP EIA Kit

SKT-209-96 Stressmarq 1 plate of 96 wells 544.8 EUR

Cyclic GMP EIA Kit

SKT-211-96 Stressmarq 1 plate of 96 wells 568.8 EUR

Cyclic AMP [HRP]

DAG1077 Creative Diagnostics 0.5ml 858 EUR

Cyclic di-GMP

B7839-.5 ApexBio 500 µg 217.2 EUR

Cyclic di-GMP

B7839-1 ApexBio 1 mg 362.4 EUR


B2045-1000 Biovision each 666 EUR


B2045-250 Biovision each 248.4 EUR


HY-107780 MedChemExpress 10mM/1mL 4454.4 EUR

Cyclic AMP Antibody

abx022638-02ml Abbexa 0.2 ml 1161.6 EUR

Cyclic GMP Antibody

abx022640-02ml Abbexa 0.2 ml 1128 EUR

Pifithrin-?, Cyclic, hydrobromide

2270-5 Biovision each 274.8 EUR

Cyclic Pifithrin-? hydrobromide

A4477-10 ApexBio 10 mg 189.6 EUR

Cyclic Pifithrin-? hydrobromide

A4477-25 ApexBio 25 mg 366 EUR

Cyclic Pifithrin-? hydrobromide

A4477-5 ApexBio 5 mg 135.6 EUR

Cyclic Pifithrin-? hydrobromide

A4477-50 ApexBio 50 mg 595.2 EUR

Cyclic AMP Standard, 125UL

C066-125UL Arbor Assays 125UL 85 EUR

Cyclic AMP Standard, 625UL

C066-625UL Arbor Assays 625UL 203 EUR

Cyclic GMP Standard, 125UL

C080-125UL Arbor Assays 125UL 85 EUR

Cyclic GMP Standard, 350UL

C080-350UL Arbor Assays 350UL 207 EUR

Cyclic GMP Standard, 625UL

C080-625UL Arbor Assays 625UL 207 EUR

Cyclic GMP Standard, 70UL

C080-70UL Arbor Assays 70UL 85 EUR

Cyclic Diadenylate Monophosphate

VAdv-Ly0021 Creative Biolabs 1 mg 2274 EUR

Propane 1,2-Cyclic Sulfate

20-abx184324 Abbexa
  • 510.00 EUR
  • 276.00 EUR
  • 25 g
  • 5 g

ELISA kit for cGMP (Cyclic GMP)

E-EL-0083 Elabscience Biotech 1 plate of 96 wells 452.4 EUR

Cyclic AMP and c-KIT signaling in familial testicular germ cell tumor predisposition.

Familial testicular germ cell tumors (FTGCTs) are hypothesized to result from the combined interaction of multiple low-penetrance genes. We reported inactivating germline mutations of the cAMP-binding phosphodiesterase 11A (PDE11A) as modifiers of FTGCT risk. Recent genome-wide association studies have identified single-nucleotide polymorphisms in the KITLG gene, the ligand for the cKIT tyrosine kinase receptor, as strong modifiers of susceptibility to both familial and sporadic testicular germ cell tumors.
We studied 94 patients with FTGCTs and 50 at-risk male relatives from 63 unrelated kindreds, in whom the PDE11A gene had been sequenced by investigating the association between KITLG genome-wide association study single-nucleotide polymorphisms rs3782179 and rs4474514 and FTGCT risk in these patients and in 692 controls. We also examined cAMP and c-KIT signaling in testicular tissues and cell lines and extended the studies to 2 sporadic cases, one with a PDE11A defect and one without, as a comparison.
We found a higher frequency of the KITLG risk alleles in FTGCT patients who also had a PDE11A sequence variant, compared with those with a wild-type PDE11A sequence. In NTERA-2 and Tcam-2 cells transfected with the mutated forms of PDE11A (R52T, F258Y, Y727C, R804H, V820M, R867G, and M878V), cAMP levels were significantly higher, and the relative phosphodiesterase activity was lower than in the wild-type cells. KITLG expression was consistently increased in the presence of PDE11A-inactivating defects, both at the RNA and protein levels, in familial testicular germ cell tumors. The 2 sporadic cases that were studied, one with a PDE11A defect and another without, agreed with the data in FTGTCT and in the cell lines.
Patients with FTGCT and PDE11A defects also carry KITLG risk alleles more frequently. There may be an interaction between cAMP and c-KIT signaling in predisposition to testicular germ cell tumors.

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