Colon cancer cells contain high levels of cystathionine-β-synthase (CBS). Its product, hydrogen sulfide (H 2 S), promotes the growth and proliferation of colorectal tumor cells. To improve the antitumor efficacy of the prototypical CBS inhibitor aminooxyacetic acid (AOAA), we have designed and synthesized YD0171, a methyl ester derivative of AOAA. The antiproliferative effect of YD0171 exceeded the antiproliferative potency of AOAA in HCT116 human colon cancer cells. The esterase inhibitor paraoxon prevented the cellular inhibition of CBS activity by YD0171. YD0171 suppressed mitochondrial respiration and glycolytic function and induced G0/G1 arrest, but did not induce tumor cell apoptosis or necrosis. Metabolomic analysis in HCT116 cells showed that YD0171 affects multiple pathways of cell metabolism. The efficacy of YD0171 as an inhibitor of tumor growth was also tested in nude mice bearing subcutaneous HCT116 cancer cell xenografts. Animals were treated via subcutaneous injection of vehicle or AOAA (0.1, 0.5 or 1 mg/kg/d) for 3 wks. Tumor growth was significantly reduced by 9 mg/kg/d AOAA, but not at the lower doses. YD0171 was more potent: tumor volume was significantly inhibited at 0.5 and 1 mg/kg/d. Thus, the in vivo efficacy of YD0171 is nine times higher than that of AOAA. YD0171 (1 mg/kg/d) attenuated tumor growth and metastasis formation in the intracecal HCT116 tumor model. YD0171 (3 mg/kg/d) also reduced tumor growth in patient-derived tumor xenograft bearing athymic mice. YD0171 (3 mg/kg/d) induced the regression of established HCT116 tumors in vivo. A 5-d safety study in mice demonstrated that YD0171 at 20 mg/kg/d (given in two divided doses) does not increase plasma markers of organ injury, nor does it induce histological alterations in the liver or kidney. YD0171 caused a slight elevation in plasma homocysteine levels. In conclusion, the prodrug approach improves the pharmacological profile of AOAA; YD0171 represents a prototype for CBS inhibitory anticancer prodrugs. By targeting colorectal cancer bioenergetics, an emerging important hallmark of cancer, the approach exemplified herein may offer direct translational opportunities.

Background Sepsis remains the largest preventable source of neonatal mortality in the world. Heart rate variability (HRV) analysis and noninvasive cardiac output, have been shown to be useful adjuncts to sepsis detection in many patient groups. Methods With IRB approval, 4 septic and 6 nonseptic ELBW patients were enrolled. Data from septic and healthy patients were collected for 5 hours. ECG waveform and traditional vital signs were collected and the RR intervals were calculated, then heart rate variability analysis was performed in both the time- and frequency-domain. Results HRV measurements in time-domain, HR, and Sp02 were significantly different in septic patients vs. nonseptic controls Conclusion These results indicate that nonconventional vital signs such as HRV are more sensitive than traditionally used vital signs, such as CO and MAP, in the confirmation of sepsis in ELBW neonates. HRV may allow for earlier identification of septic physiology.

BACKGROUND Chronic pancreatitis (CP) is characterized by recurrent pancreatic injury, resulting in inflammation, necrosis, and fibrosis. There are currently no drugs limiting pancreatic fibrosis associated with CP, and there is a definite need to fill this void in patient care. MATERIALS AND METHODS Pancreatitis was induced in C57/BL6 mice using supraphysiologic doses of cerulein (CR), and apigenin treatment (once daily, 50 μg/mouse by oral gavage) was initiated one week into the recurrent acute pancreatitis (RAP) protocol. Pancreata were harvested after four weeks of RAP. Immunostaining with fibronectin antibody was used to quantify the extent of pancreatic fibrosis. To assess how apigenin may decrease organ fibrosis, we evaluated the effect of apigenin on the proliferation and apoptosis of human pancreatic stellate cells (PSCs) in vitro. Lastly, we assessed apigenin’s effect on gene expression in PSCs stimulated with parathyroid hormone related protein (PTHrP), a pro-fibrotic and pro-inflammatory mediator of pancreatitis, using RT-PCR. RESULTS After four weeks of RAP, apigenin significantly reduced the fibrotic response to injury while preserving acinar units. Apigenin inhibited viability and induced apoptosis of PSCs in a time and dose-dependent manner. Lastly, apigenin reduced PTHrP-stimulated increases in the PSC mRNA expression levels of extracellular matrix proteins collagen 1A1 and fibronectin, proliferating cell nuclear antigen, TGF-β, and IL-6. CONCLUSIONS These in vivo and in vitro studies provide novel insights regarding apigenin’s mechanism(s) of action in reducing the severity of RAP. Additional preclinical testing of apigenin analogs is warranted to develop a therapeutic agent for patients at risk for CP.

Accumulating evidence suggests that activated pancreatic stellate cells (PSC) play an important role in chronic pancreatitis (CP), and inhibition of the activated PSC is considered as a potential strategy for the treatment and prevention of CP. Herein, we disclose our findings that apigenin and its novel analogues suppress the proliferation and induce apoptosis in PSC which reduce the PSC-mediated fibrosis in CP. Chemical modifications of apigenin have been directed to build a focused library of O-alkylamino-tethered apigenin derivatives at 4′-O position of the ring C with the attempt to enhance the potency and drug-like properties including aqueous solubility. A number of compounds such as 14, 16, and 24 exhibited potent antiproliferative effects as well as improved aqueous solubility. Intriguingly, apigenin, new analogues 23 and 24 displayed significant efficacy to reduce pancreatic fibrosis even at a low dose of 0.5 mg/kg in our proof-of-concept study using a preclinical in vivo mouse model of CP.

Sepsis is a life-threatening clinical condition that is particularly serious among the elderly who experience considerably higher mortality rates compared with younger patients. Using a sterile endotoxemia model, we previously reported age-dependent mortality in conjunction with enhanced coagulation and insufficient levels of anti-coagulant factor activated protein C (aPC). The purpose of the present study was to further investigate the mechanisms for age-dependent coagulation and aPC insufficiency during experimental sepsis. Intra-abdominal sepsis was induced by cecal ligation and puncture (CLP) using 21 or 16 gauge (G) needles (double-puncture) on young (4 to 6 mo old) and aged (20 to 25 mo old) male C57BL/6 mice. When compared with young mice, aged mice showed significantly increased mortality (92% vs. 28%), systemic inflammation, and coagulation in the lung and kidney after 21G CLP. Young mice with more severe CLP (16G) showed a mortality rate and inflammation equivalent to aged mice with 21G CLP; however, enhanced coagulation and kidney dysfunction were significant only in the aged. In young mice, increased levels of aPC after CLP were coupled with reduced levels of protein C (PC), suggesting the conversion of PC to aPC; however, PC and aPC levels remained unchanged in aged mice, indicating a lack of PC to aPC conversion. Activation of fibrinolysis, determined by plasma d-dimer levels, was similar regardless of age or CLP severity, and plasminogen activator inhibitor-1, an inhibitor of fibrinolysis, showed severity-dependent induction independent of age. These results suggest that enhanced coagulation in aged mice during sepsis is due to dysfunction of the PC activation mechanism.