A Multimodal Theranostic System Prepared from High-Density Lipoprotein Carrier of Doxorubicin and 177Lu

Recently, it was demonstrated that doxorubicin (Dox.HCl), a chemotherapeutic agent, could be photoactivated by Cerenkov radiation (CR). The objective of the present work was to develop a multimodal chemotherapy-radiotherapy-photodynamic therapeutic system based on reconstituted high-density lipoprotein (rHDL) loaded with Dox.HCl and 177Lu-DOTA. 177Lu acts as a therapeutic radionuclide and CR source. The system can be visualized by nuclear imaging. Fluorescence microscopy showed that rHDL-Dox specifically recognized cancer cells (T47D) that are positive for SR-B1 receptors. Encapsulated Dox.HCl was released into the cells and produced reactive oxygen species when irradiated with a 450-nm laser (photodynamic effect). The same effect occurred when Dox.HCl was irradiated by 177Lu CR. Through in vitro experiments, it was confirmed that the addition of 177Lu-DOTA to the rHDL-Dox nanosystem did not affect the specific recognition of SR-B1 receptors expressed in cells, or the cellular internalization of 177Lu-DOTA. The toxicity induced by the rHDL-Dox/177Lu nanosystem in cell lines with high (T47D and PC3), poor (H9C2) and almost-zero (human fibroblasts (FB)) expression of SR-B1 was evaluated in vitro and confirmed the synergy of the combined chemotherapy-radiotherapy-photodynamic therapeutic effect; this induced toxicity was proportional to the expression of the SR-B1 receptor on the surface of the cells used. The HDL-Dox/177Lu nanosystem experienced uptake by tumor cells and the liver-both tissues with high expression of SR-B1 receptors-but not by the heart. 177Lu CR offered the possibility of imparting photodynamic therapy where laser light could not reach.

Reversal of pulmonary arterial hypertension and neointimal formation by kinin B1 receptor blockade

Background This study examined whether BI113823, a novel selective kinin B1 receptor antagonist can reverse established pulmonary arterial hypertension (PAH), prevent right heart failure and death, which is critical for clinical translation. Methods Left pneumonectomized male Wistar rats were injected with monocrotaline to induce PAH. Three weeks later, when PAH was well established, the rats received daily treatment of BI113823 or vehicle for 3 weeks. Results Treatment with BI113823 from day 21 to day 42 after monocrotaline injection reversed established PAH as shown by normalized values of mean pulmonary arterial pressure (mPAP). BI113823 therapy reversed pulmonary vascular remodeling, pulmonary arterial neointimal formation, and heart and lung fibrosis, reduced right ventricular pressure, right heart hypertrophy, improved cardiac output, and prevented right heart failure and death. Treatment with BI113823 reduced TNF-α and IL-1β, and macrophages recruitment in bronchoalveolar lavage, reduced CD-68 positive macrophages and expression of proliferating cell nuclear antigen (PCNA) in the perivascular areas, and reduced expression of iNOS, B1 receptors, matrix metalloproteinase (MMP)-2 and MMP-9 proteins, and the phosphorylation of ERK1/2 and AKT in lung. Treatment with BI113823 reduced mRNA expression of ANP, BNP, βMHC, CGTF, collange-I and IV in right heart, compared to vehicle treated controls. In human monocytes cultures, BI113823 reduced LPS-induced TNF-α production, MMP-2 and MMP-9 expression, and reduced TNF-α-induced monocyte migration. Conclusions We conclude that BI113823 reverses preexisting severe experimental pulmonary hypertension via inhibition of macrophage infiltration, cytokine production, as well as down regulation of matrix metalloproteinase proteins.

Hypothalamic kinin B1 receptor mediates orexin system hyperactivity in neurogenic hypertension

Brain orexin system hyperactivity contributes to neurogenic hypertension. We previously reported upregulated neuronal kinin B1 receptor (B1R) expression in hypertension. However, the role of central B1R activation on the orexin system in neurogenic hypertension has not been examined. We hypothesized that kinin B1R contributes to hypertension via upregulation of brain orexin-arginine vasopressin signaling. We utilized deoxycorticosterone acetate (DOCA)-salt hypertension model in wild-type (WT) and B1R knockout (B1RKO) mice. In WT mice, DOCA-salt-treatment increased gene and protein expression of orexin A, orexin receptor 1, and orexin receptor 2 in the hypothalamic paraventricular nucleus and these effects were attenuated in B1RKO mice. Furthermore, DOCA-salt- treatment increased plasma arginine vasopressin levels in WT mice, but not in B1RKO mice. Cultured primary hypothalamic neurons expressed orexin A and orexin receptor 1. B1R specific agonist (LDABK) stimulation of primary neurons increased B1R protein expression, which was abrogated by B1R selective antagonist R715 but not by the dual orexin receptor antagonist, ACT 462206, suggesting that B1R is upstream of the orexin system. These data provide novel evidence that B1R blockade blunts orexin hyperactivity and constitutes a potential therapeutic target for the treatment of salt-sensitive hypertension.

Novel Bradykinin Receptor Inhibitors Inhibit Proliferation and Promote the Apoptosis of Hepatocellular Carcinoma Cells by Inhibiting the ERK Pathway

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide. Studies have shown that bradykinin (BK) is highly expressed in liver cancer. We designed the novel BK receptor inhibitors J051-71 and J051-105, which reduced the viability of liver cancer cells and inhibited the formation of cancer cell colonies. J051-71 and J051-105 reduced cell proliferation and induced apoptosis in HepG2 and BEL-7402 cells, which may be due to the inhibition of the extracellular regulated protein kinase (ERK) signaling pathway. In addition, these BK receptor inhibitors reversed the cell proliferation induced by BK in HepG2 and BEL-7402 cells by downregulating B1 receptor expression. Inhibiting B1 receptor expression decreased the protein levels of p-ERK and reduced the malignant progression of HCC, providing a potential target for HCC therapy.

MO067DELETION AND BLOCKAGE OF KININ B1 RECEPTOR EXACERBATES CISPLATIN-INDUCED CKD

Background and Aims Kinins plays a major role in immune response, where kinin B2 receptor is constitutively expressed and kinin B1 receptor is induced under inflammatory stimuli. Kinin B1 receptor deletion and blockage has been shown to have beneficial effects in some models of renal diseases. Multiple acute renal insults, even if followed by renal recovery, is a risk factor for the future development of chronic kidney disease (CKD) and end-stage renal disease (ESRD). Our main objective was to determine the importance of kinin B1 receptor in tubulointerstitial fibrosis induced by ongoing cisplatin treatment. Method Male C57/Bl6 mice were divided in 3 groups, vehicle, cisplatin, cisplatin + R715 (kinin B1 receptor antagonist). Animals has been treated with multiple doses of cisplatin (7mg/kg i.p) once a week during 4 weeks and R715 (0.8mg/kg i.p) 48, 24 and 1 hour prior to cisplatin injections. We also used B1KO mice (C57Bl6 background) and WT mice (littermates). Mice were euthanized after 30 days of last cisplatin injection. Renal parameters, histology, real time PCR were performed to investigate renal injury, inflammation and fibrosis. Results Cisplatin treatment increases most of renal parameters, renal injury and fibrosis markers. Deletion of B1 receptor exacerbates significantly creatinine (WT CIS 0,60+0,03 B1KO 0,76+0,01 mg/dL), urea (WT CIS 111,8+5,638 B1KO CIS 240,8+28,60 mg/dL), and protein excretion (WT CIS 0,0058+0,0011 B1KO CIS 0,0121+0,0007 mg/24h). Association of cisplatin with R715 increased creatinine levels (veh 0,43+0,03 cis+R715 0,64+0,04 mg/dL), exacerbates urea (cis 95,51 + 3,926 cis+R715 158,9+14,40 mg/dL) and protein excretion (cis 0,012+0,002 cis+R715 0,018+0,003 mg/24h). Renal injury markers such as KIM-1 and TNF-a showed no significant differences. NGAL expression exacerbates (cis 2,53+0,44 cis+R715 5,66+1,34) and tubular injury score (cis 0,130+0,021 cis+R715 0,191+0,020) is higher in cisplatin+R715 group. Fibrosis markers a-SMA (cis 2,56+0,43 cis+R715 4,67+0,99), Col4 (cis 2,57+0,39 cis+R715 5,14+1,01) and Vimentin (2,69+0,31 cis+R715 4,62+0,98) were exacerbated in cisplatin treatment associated with R715. Picrosirius red staining were used to asses tubulointerstitial fibrosis, and we confirmed that R715 treatment here also exacerbates fibrosis (cis 0,225+0,025 cis+R715 0,345+0,042). Conclusion Here we show that both deletion and blockage of kinin B1 receptor has deleterious effects in renal injury and fibrosis induced by ongoing cisplatin treatment.