Targeting of intragraft reactive oxygen species by APP-103, a novel polymer product, mitigates ischemia/reperfusion injury and promotes the survival of renal transplants.

Inflammatory responses associated with ischemia/reperfusion injury (IRI) play a central role in alloimmunity and transplant outcomes. A key event driving these inflammatory responses is the burst of reactive oxygen species (ROS), with hydrogen peroxide (H2 O2 ) as the most abundant form that occurs as a result of surgical implantation of the donor organ. Here, we used a syngeneic rat renal transplant and IRI model to evaluate the therapeutic properties of APP-103, a polyoxalate-based copolymer molecule containing vanillyl alcohol (VA) that exhibits high sensitivity and specificity toward the production of H2 O2 . We show that APP-103 is safe, and that it effectively promotes kidney function following IRI and survival of renal transplants. APP-103 reduces tissue injury and IRI-associated inflammatory responses in models of both warm ischemia (kidney clamping) and prolonged cold ischemia (syngeneic renal transplant). Mechanistically, we demonstrate that APP-103 exerts protective effects by specifically targeting the production of ROS. Our data introduce APP-103 as a novel, nontoxic, and site-activating therapeutic approach that effectively ameliorates the consequences of IRI in solid organ transplantation.

Mitochondria to nucleus translocation of AIF in mice lacking Hsp70 during ischemia/reperfusion.

Heat shock protein 70 (Hsp70) has been shown to have an anti-apoptotic function, but its mechanism is not clear in heart. In this study, we examined the effect of Hsp70 deletion on AIF-induced apoptosis during ischemia/reperfusion (I/R) in vivo. Although Hsp70 KO and WT mice demonstrated similar amounts of AIF released from mitochondria after I/R surgery, Hsp70 KO mice showed a significantly greater increase in apoptosis, larger infarct size, and decreased cardiac output. There was also a significant fourfold increase in the nuclear accumulation of AIF in Hsp70 KO mice compared with WT mice. Treatment with 4-AN (4-amino-1,8-napthalimide, 3 mg/kg), a potent inhibitor of PARP-1, which is a critical regulator of AIF-induced apoptosis, significantly blocked the release of AIF from mitochondria and the translocation of AIF into the nuclei after I/R in both WT and Hsp70 KO mice. In addition, 4-AN treatment resulted in a significant inhibition of apoptosis, a reduction of infarct size, and attenuated cardiac dysfunction in both WT and Hsp70 KO mice after I/R. The anti-apoptotic function of Hsp70 occurs through the inhibition of AIF-induced apoptosis by blocking the mitochondria to nucleus translocation of AIF. PARP-1 inhibition improves cardiac function by blocking AIF-induced apoptosis.

Doxercalciferol, a pro-hormone of vitamin D, prevents the development of cardiac hypertrophy in rats.

BACKGROUND: Activated vitamin D analog, paricalcitol, has been shown to attenuate the development of cardiac hypertrophy in Dahl salt sensitive (DSS) rats. To determine whether an antihypertrophic effect is class specific, we tested if doxercalciferol (a pro-hormone vitamin D2 analog) could also attenuate the development of cardiac hypertrophy in DSS rats. METHODS AND RESULTS: Male DSS rats were fed a high salt (HS) diet for 6 weeks beginning at 6 weeks of age. Doxercalciferol was administered intraperitoneally at 150 ng, 3 times per week (Monday, Wednesday, Friday) for 6 weeks. Pathological and echocardiographic findings demonstrated that rats on HS diet with doxercalciferol administration had significant decrease in cardiac hypertrophy and improved cardiac function compared to the HS + vehicle. In addition, there was a significant decrease in plasma brain natriuretic peptide (BNP) level and tissue atrial natriuretic factor (ANF) mRNA level with doxercalciferol treatment. Doxercalciferol also significantly reduced the level of protein kinase C-α (PKCα) suggesting that PKC-mediated cardiac hypertrophy may be associated with vitamin D deficiency. CONCLUSIONS: Administration of doxercalciferol attenuated the development of HS diet induced cardiac hypertrophy and cardiac dysfunction in DSS rats.

Bilirubin Nanoparticles Protect Against Cardiac Ischemia/Reperfusion Injury in Mice.

Background Ischemia/reperfusion (I/R) injury causes overproduction of reactive oxygen species, which are the major culprits of oxidative stress that leads to inflammation, apoptosis, myocardial damage, and dysfunction. Bilirubin acts as a potent endogenous antioxidant that is capable of scavenging various reactive oxygen species. We have previously generated bilirubin nanoparticles (BRNPs) consisting of polyethylene glycol-conjugated bilirubin. In this study, we examined the therapeutic effects of BRNPs on myocardial I/R injury in mice. Methods and Results In vivo imaging using fluorophore encapsulated BRNPs showed BRNPs preferentially targeted to the site of I/R injury in the heart. Cardiac I/R surgery was performed by first ligating the left anterior descending coronary artery. After 45 minutes, reperfusion was achieved by releasing the ligation. BRNPs were administered intraperitoneally at 5 minutes before and 24 hours after reperfusion. Mice that received BRNPs showed significant improvements in their cardiac output, assessed by echocardiogram and pressure volume loop measurements, compared with the ones that received vehicle treatment. BRNPs treatment also significantly reduced the myocardial infarct size in mice that underwent cardiac I/R, compared with the vehicle-treatment group. In addition, BRNPs effectively suppressed reactive oxygen species and proinflammatory factor levels, as well as the amount of cardiac apoptosis. Conclusions Taken together, BRNPs could exert their therapeutic effects on cardiac I/R injury through attenuation of oxidative stress, apoptosis, and inflammation, providing a novel therapeutic modality for myocardial I/R injury.

H2O2-Responsive Antioxidant Nanoparticle Attenuates Whole Body Ischemia/Reperfusion-Induced Multi-Organ Damages.

Mortality and morbidity after cardiac arrest remain high due to ischemia/reperfusion (I/R) injury causing multi-organ damages, even after successful return of spontaneous circulation. We previously generated H2O2-activatable antioxidant nanoparticles formulated with copolyoxalate containing vanillyl alcohol (PVAX) to prevent I/R injury. In this study, we examined whether PVAX could effectively reduce organ damages in a rat model of whole-body ischemia/reperfusion injury (WBIR). To induce a cardiac arrest, 70µl/100 g body weight of 1 mmol/l potassium chloride was administered via the jugular venous catheter. The animals in both the vehicle and PVAX-treated groups had similar baseline blood pressure. After 5.5 minutes of cardiac arrest, animals were resuscitated via intravenous epinephrine followed by chest compressions. PVAX or vehicle was injected after the spontaneous recovery of blood pressure was noted, followed by the same dose of second injection 10 minutes later. After 24 hours, multiple organs were harvested for pathological, biochemical, molecular analyses. No significant difference on the restoration of spontaneous circulation was observed between vehicle and PVAX groups. Analysis of organs harvested 24 hours post procedure showed that whole body I/R significantly increased reactive oxygen species (ROS) generation, inflammatory markers, and apoptosis in multiple organs (heart, brain, and kidney). PVAX treatment effectively blocked ROS generation, reduced the elevation of pro-inflammatory cytokines, and decreased apoptosis in these organs. Taken together, our results suggest that PVAX has potent protective effect against WBIR induced multi-organ injury, possibly by blocking ROS-mediated cell damage.

Delayed activation of caspase-independent apoptosis during heart failure in transgenic mice overexpressing caspase inhibitor CrmA.

Although caspase activation is generally thought to be necessary to induce apoptosis, recent evidence suggests that apoptosis can be activated in the setting of caspase inhibition. In this study, we tested the hypothesis that caspase-independent apoptotic pathways contribute to the development of heart failure in the absence of caspase activation. Acute cardiomyopathy was induced using a single dose of doxorubicin (Dox, 20 mg/kg) injected into male wild-type (WT) and transgenic (Tg) mice with a cardiac-specific expression of cytokine response modifier A (CrmA), a known caspase inhibitor. Early (6 day) survival was significantly better in CrmA Tg (81%) than WT (38%) mice. Twelve days after Dox injection, however, the mortality benefit had dissipated, and increased cardiac apoptosis was observed in both groups. There was, however, a significantly greater release of apoptosis-inducing factor (AIF) from mitochondria to cytosol in CrmA Tg compared with WT mice, which suggests that an enhancement of activation in caspase-independent apoptotic pathways had occurred. The administration of a poly(ADP-ribose) polymerase-1 inhibitor, 4-amino-1,8-naphthalimide (4-AN), to Dox-treated mice resulted in significantly improved cardiac function, a significant blockade of AIF released from mitochondria, and decreased cardiac apoptosis. There were also significantly improved survival in WT (18% without 4-AN vs. 89% with 4-AN) and CrmA Tg (13% without 4-AN vs. 93% with 4-AN) mice 12 days after Dox injection. In conclusion, these findings suggest that apoptosis can be induced in the heart lacking caspase activation via caspase-independent pathways and that enabling the inhibition of AIF activation may provide a significant cardiac benefit.

Exacerbation of acute viral myocarditis by tobacco smoke is associated with increased viral load and cardiac apoptosis.

Exposure to tobacco smoke is known to have deleterious cardiovascular effects. In this study, we tested whether exposure to tobacco smoke exacerbates the severity of viral myocarditis in mice. Viral myocarditis was generated in 4-week-old male BALB/c mice by injection of Encephalomyocarditis virus (EMCV). Four groups were studied: (1) control (C, no smoke and no virus); (2) smoke only (S, exposure to cigarette smoke for 90 min/day for 15 days); (3) virus only (V); and (4) exposure to smoke for 5 days before plus 10 days following virus injection (S+V). We found that viral inoculation preceded by smoke exposure increased mortality more than twofold compared with virus inoculation alone. In addition, the mRNA level of atrial natriuretic factor was significantly higher in S+V than among any of the other 3 groups. Virus injection significantly decreased cardiac function compared with controls, with further deterioration observed in the S+V group. We also observed a significantly increased rate of apoptosis, with an increased activation of apoptosis-inducing factor in hearts exposed to S+V compared with those exposed to V alone. Our results suggest that preexposure to smoke significantly exacerbates the severity of viral myocarditis, likely through increased viral load and increased cardiomyocyte cell death.

Neuropeptide Y3-36 incorporated into PVAX nanoparticle improves angiogenesis in a murine model of myocardial ischemia.

Neuropeptide-Y (NPY) leads to angiogenesis and remodeling of the ischemic myocardium. The objective of this study is to assess the therapeutic potential of NPY in a model of acute myocardial ischemia using a nanoparticles delivery system targeted to tissue with oxidative stress. NPY3-36 was loaded onto copolyoxalate containing vanillyl alcohol (PVAX) using a double emulsification strategy. Adult C57BL/J6 mice (n = 49) were randomly divided into PVAX-NPY3-36 (n = 22), Vehicle (Saline) (n = 16), and Sham (n = 11) groups. The ischemia to left anterior descending artery was induced in PVAX-NPY3-36 or vehicle groups. The tissue was collected at the end of two weeks after assessing the functional and echocardiographic data. There was a significant decrease in infarction size and mortality in PVAX-NPY3-36 group compared to the Vehicle group (P = 0.01 and P = 0.05). On echocardiography, there was significant improvement in contractility and diastolic parameters (P = 0.01). On pressure-volume loop there was significant increase in stroke volume (P = 0.01), cardiac output (P = 0.01) and ventricular stroke work (P = 0.01) in the PVAX-NPY3-36 group. On Western blot analysis, there was a significant increase in pro-angiogenic factors Ang-1, TGF-ß, PDGF- ß and its receptors and VEGF in the ischemic tissue treated with PVAX-NPY3-36 as compared to Vehicle ischemic tissue (P = 0.01, P = 0.0003, and P < 0.05 respectively). It may be possible to have targeted delivery of labile neurotransmitters NPY3-36 to the ischemic myocardium using nanoparticle PVAX and achieving angiogenesis and significant functional improvement.

Role of caspase-independent apoptosis in cardiovascular diseases.

Apoptosis plays an important role in various cardiovascular diseases, and inhibition of cardiac apoptosis shows promise as a therapeutic strategy. Caspase, a critical enzyme in the induction and execution of apoptosis, has been targeted to inhibit apoptosis. However a newly recognized caspase-independent apoptosis pathway may also play an important role in cardiac apoptosis. Yet the mechanism and the potential significance of caspase-independent apoptosis in the heart remain poorly understood. In this paper, we reviewed the literatures on the mechanism of caspase-independent apoptosis and its significance in cardiovascular diseases.

Use of Plant and Herb Derived Medicine for Therapeutic Usage in Cardiology.

Cardiovascular diseases (CVDs) have become prominent in mortality and morbidity rates. Prevalent cardiovascular conditions, such as hypertension, atherosclerosis and oxidative stress, are increasing at an alarming rate. Conventional drugs have been associated with adverse effects, suggesting a need for an alternative measure to ameliorate CVD. A number of plant- and herb-derived preventative food and therapeutic drugs for cardiovascular conditions are progressively used for their various benefits. Naturally derived food and drugs have fewer side effects because they come from natural elements; preventative food, such as grape seed, inhibits changes of histopathology and biomarkers in vital organs whereas therapeutic drugs, for instance Xanthone, improve heart functions by suppressing oxidative stress of myocyte. This review closely examines the various plant- and herb-derived drugs that have assumed an essential role in treating inflammation and oxidative stress for prevalent cardiovascular conditions. Furthermore, the use of plant-derived medicine with other synthetic particles, such as nanoparticles, for targeted therapy is investigated for its effective clinical use in the future.

Highly conductive, stretchable and biocompatible Ag-Au core-sheath nanowire composite for wearable and implantable bioelectronics.

Wearable and implantable devices require conductive, stretchable and biocompatible materials. However, obtaining composites that simultaneously fulfil these requirements is challenging due to a trade-off between conductivity and stretchability. Here, we report on Ag-Au nanocomposites composed of ultralong gold-coated silver nanowires in an elastomeric block-copolymer matrix. Owing to the high aspect ratio and percolation network of the Ag-Au nanowires, the nanocomposites exhibit an optimized conductivity of 41,850 S cm-1 (maximum of 72,600 S cm-1). Phase separation in the Ag-Au nanocomposite during the solvent-drying process generates a microstructure that yields an optimized stretchability of 266% (maximum of 840%). The thick gold sheath deposited on the silver nanowire surface prevents oxidation and silver ion leaching, making the composite biocompatible and highly conductive. Using the nanocomposite, we successfully fabricate wearable and implantable soft bioelectronic devices that can be conformally integrated with human skin and swine heart for continuous electrophysiological recording, and electrical and thermal stimulation.

Neuropeptide Y3-36 incorporated into PVAX nanoparticle improves functional blood flow in a murine model of hind limb ischemia.

We generated a novel nanoparticle called PVAX, which has intrinsic antiapoptotic and anti-inflammatory properties. This nanoparticle was loaded with neuropeptide Y3-36 (NPY3-36), an angiogenic neurohormone that plays a central role in angiogenesis. Subsequently, we investigated whether PVAX-NPY3-36 could act as a therapeutic agent and induce angiogenesis and vascular remodeling in a murine model of hind limb ischemia. Adult C57BL/J6 mice (n = 40) were assigned to treatment groups: control, ischemia PBS, ischemia PVAX, ischemia NPY3-36, and Ischemia PVAX-NPY3-36 Ischemia was induced by ligation of the femoral artery in all groups except control and given relevant treatments (PBS, PVAX, NPY3-36, and PVAX-NPY3-36). Blood flow was quantified using laser Doppler imaging. On days 3 and 14 posttreatment, mice were euthanized to harvest gastrocnemius muscle for immunohistochemistry and immunoblotting. Blood flow was significantly improved in the PVAX-NPY3-36 group after 14 days. Western blot showed an increase in angiogenic factors VEGF-R2 and PDGF-ß (P = 0.0035 and P = 0.031, respectively) and antiapoptotic marker Bcl-2 in the PVAX-NPY3-36 group compared with ischemia PBS group (P = 0.023). Proapoptotic marker Smad5 was significantly decreased in the PVAX-NPY3-36 group as compared with the ischemia PBS group (P = 0.028). Furthermore, Y2 receptors were visualized in endothelial cells of newly formed arteries in the PVAX-NPY3-36 group. In conclusion, we were able to show that PVAX-NPY3-36 can induce angiogenesis and arteriogenesis as well as improve functional blood flow in a murine model of hind limb ischemia.NEW & NOTEWORTHY Our research project proposes a novel method for drug delivery. Our patented PVAX nanoparticle can detect areas of ischemia and oxidative stress. Although there have been studies about delivering angiogenic molecules to areas of ischemic injury, there are drawbacks of nonspecific delivery as well as short half-lives. Our study is unique because it can specifically deliver NPY3-36 to ischemic tissue and appears to extend the amount of time therapy is available, despite NPY3-36's short half-life.

Hydrogen Peroxide-Responsive Nanoparticle Reduces Myocardial Ischemia/Reperfusion Injury.

BACKGROUND: During myocardial ischemia/reperfusion (I/R), a large amount of reactive oxygen species (ROS) is produced. In particular, overproduction of hydrogen peroxide (H2O2) is considered to be a main cause of I/R-mediated tissue damage. We generated novel H2O2-responsive antioxidant polymer nanoparticles (PVAX and HPOX) that are able to target the site of ROS overproduction and attenuate the oxidative stress-associated diseases. In this study, nanoparticles were examined for their therapeutic effect on myocardial I/R injury. METHODS AND RESULTS: The therapeutic effect of nanoparticles during cardiac I/R was evaluated in mice. A single dose of PVAX (3 mg/kg) showed a significant improvement in both cardiac output and fraction shortening compared with poly(lactic-coglycolic acid) (PLGA) particle, a non-H2O2-activatable nanoparticle. PVAX also significantly reduced the myocardial infarction/area compared with PLGA (48.7±4.2 vs 14.5±2.1). In addition, PVAX effectively reduced caspase-3 activation and TUNEL-positive cells compared with PLGA. Furthermore, PVAX significantly decreased TNF-α and MCP-1 mRNA levels. To explore the antioxidant effect of PVAX by scavenging ROS, dihydroethidium staining was used as an indicator of ROS generation. PVAX effectively suppressed the generation of ROS caused by I/R, whereas a number of dihydroethidium-positive cells were observed in a group with PLGA I/R. In addition, PVAX significantly reduced the level of NADPH oxidase (NOX) 2 and 4 expression, which favors the reduction in ROS generation after I/R. CONCLUSIONS: Taken together, these results suggest that H2O2-responsive antioxidant PVAX has tremendous potential as a therapeutic agent for myocardial I/R injury.

Prenatal cocaine exposure increases apoptosis of neonatal rat heart and heart susceptibility to ischemia-reperfusion injury in 1-month-old rat.

Maternal cocaine administration during pregnancy increased apoptosis in near-term fetal rat heart. The present study tested the hypothesis that prenatal cocaine exposure increases the heart susceptibility to ischemia/reperfusion injury in the offspring. Pregnant Sprague-Dawley rats received cocaine (30 mg kg(-1) day(-1)) or saline from days 15 to 21 of gestational age. Maternal body weights were not significantly different at the end of cocaine treatment, but body weights of offspring were decreased slightly at ages of 1, 3, and 7 days. Although heart-to-body weight ratio was not affected at all ages examined, prenatal cocaine significantly increased left ventricular myocyte size at an age of 30 days. Additionally, prenatal cocaine increased DNA fragmentation measured in the hearts isolated from offspring of 1, 3, 7, and 21 days, but not of 30 days, with the peak at 3-day neonates. Antiapoptotic (Bcl-2 and Bcl-X(L)) and proapoptotic (Bax and Bad) proteins were expressed in neonatal rat hearts of both groups. Prenatal cocaine exposure decreased levels of Bcl-2 in 21-day and increased Bax in 21- and 30-day rat hearts. In addition, hearts of 30-day-old male progeny were studied using the Langendorff preparation, and were subjected to 25 min of ischemia and 60 min of reperfusion. Preischemic baseline values of left ventricular (LV) function were the same between the two groups. However, prenatal cocaine exposure significantly attenuated postischemic recovery of LV function, and significantly increased elevated LV end diastolic pressure during reperfusion. This was associated with a significant increase in ischemia/reperfusion-induced LV myocardial infarct size. The results suggest that prenatal cocaine exposure induces abnormal apoptosis and myocyte hypertrophy in postnatal heart, leading to an increased heart susceptibility to ischemic insults in postnatal life.

Exaggerated hypertensive response to combretastatin A-4 phosphate in hypertensive rats: Effective pharmacological inhibition by diltiazem.

Combretastatin A-4 phosphate (CA4P), a tubulin depolymerizing agent, shows promise in anti-cancer therapy and is associated with dose-dependent transient hypertension. The cardiac consequence of this hypertensive effect is unknown. This study was conducted to examine the cardiotoxic effect of CA4P on a rat model of hypertension. Hypertensive rats were created by feeding a 6% high salt (HS) diet to Dahl salt sensitive (DSS) rats for 2.5weeks. Cardiac toxicity was measured using serum troponin I levels 24h after CA4P administration. In rats fed HS diet, there was a significant increase in mean arterial blood pressure (MAP) from baseline, which was further increased by 80% following CA4P administration with peak systolic blood pressure (BP) of 247mmHg. Treatment with the calcium channel blockers, diltiazem and nicardipine, completely inhibited the hypertensive effects of CA4P. Nitroglycerin or enalapril, however, failed to completely block the hypertensive effects of CA4P. CA4P injection also significantly increased the cardiac troponin I level in hypertensive rats though pretreatment with diltiazem effectively blocked troponin I increase after CA4P administration. Based on these findings, an exaggerated hypertensive response to CA4P is associated with myocardial damage in hypertensive rats. Calcium channel blockers effectively blocked both CA4P induced hypertension and cardiac damage.

Hydrogen peroxide-activatable antioxidant prodrug as a targeted therapeutic agent for ischemia-reperfusion injury.

Overproduction of hydrogen peroxide (H2O2) causes oxidative stress and is the main culprit in the pathogenesis of ischemia/reperfusion (I/R) injury. Suppression of oxidative stress is therefore critical in the treatment of I/R injury. Here, we report H2O2-activatable antioxidant prodrug (BRAP) that is capable of specifically targeting the site of oxidative stress and exerting anti-inflammatory and anti-apoptotic activities. BRAP with a self-immolative boronic ester protecting group was designed to scavenge H2O2 and release HBA (p-hydroxybenzyl alcohol) with antioxidant and anti-inflammatory activities. BRAP exerted potent antioxidant and anti-inflammatory activity in lipopolysaccharide (LPS)- and H2O2-stimulated cells by suppressing the generation of ROS and pro-inflammatory cytokines. In mouse models of hepatic I/R and cardiac I/R, BRAP exerted potent antioxidant, anti-inflammatory and anti-apoptotic activities due to the synergistic effects of H2O2-scavenging boronic esters and therapeutic HBA. In addition, administration of high doses of BRAP daily for 7 days showed no renal or hepatic function abnormalities. Therefore BRAP has tremendous therapeutic potential as H2O2-activatable antioxidant prodrug for the treatment of I/R injuries.

p-Hydroxybenzyl alcohol-containing biodegradable nanoparticle improves functional blood flow through angiogenesis in a mouse model of hindlimb ischemia.

Therapeutic angiogenesis has achieved promising results for ischemic diseases or peripheral artery disease in preclinical and early-phase clinical studies. We examined the therapeutic angiogenic effects of HPOX, which is biodegradable polymer composing the antioxidant p-hydroxybenzyl alcohol (HBA), in a mouse model of hindlimb ischemia. HPOX effectively stimulated blood flow recovery, compared with its degraded compounds HBA and 1,4-cyclohexendimethanol, via promotion of capillary vessel density in the ischemic hindlimb. These effects were highly correlated with levels of angiogenic inducers, vascular endothelial cell growth factor (VEGF), heme oxygenase-1 (HO-1), and Akt/AMPK/endothelial nitric oxide synthase (eNOS) in ischemic mouse hindlimb muscle. Blood perfusion and neovascularization induced by HPOX were reduced in eNOS(-/-) and HO-1(+/-) mice. HPOX also elevated the endothelial cell markers VEGF receptor-2, CD31, and eNOS mRNAs in the ischemic hindlimb, indicating that HPOX increases endothelial cell population and angiogenesis in the ischemic muscle. However, this nanoparticle suppressed expression levels of several inflammatory genes in ischemic tissues. These results suggest that HPOX significantly promotes angiogenesis and blood flow perfusion in the ischemic mouse hindlimb via increased angiogenic inducers, along with suppression of inflammatory gene expression. Thus, HPOX can be used potentially as a noninvasive drug intervention to facilitate therapeutic angiogenesis.

Comparative anti-inflammatory effects of anti-arthritic herbal medicines and ibuprofen.

Non-steroidal anti-inflammatory drugs (NSAIDS), such as ibuprofen, are widely used over-the-counter drugs to treat arthritis, but they are often associated with side effects. Herbal medicines have been used to treat various diseases such as arthritis, but the scientific profiles are not well understood. In this study, we examined, in comparison with ibuprofen, the inhibitory effects on various inflammatory markers of the most commonly used herbal medicines to treat arthritis, boswellia (Boswellia sapindales), licorice (Glycyrrhiza glabra), guggul (Commiphora wightii), and neem (Azadirachta indica). To elicit inflammatory response, we exposed mouse myoblast C2C12 cells to lipopolysaccharide (LPS). Tumor necrosis factor-alpha (TNF-α) and monocyte chemotactic protein-1 (MCP-1), which are cytokines activated during an inflammatory response, were determined. The optimal non-toxic concentration was determined by exposing different concentrations of drugs (from 0.01 to 10 mg/mL). Cell death measurement revealed that the drug concentrations lower than 0.05 mg/mL were non-toxic concentrations for each drug, and these doses were used for the main experiments. We found that neem and licorice showed robust anti-inflammatory responses compared with ibuprofen. However, boswellia and guggul did not demonstrate significant anti-inflammatory responses. We concluded that neem and licorice are more effective than ibuprofen in suppressing LPS-induced inflammation in C2C12 cells.

Abnormal calcium handling and exaggerated cardiac dysfunction in mice with defective vitamin d signaling.

AIM: Altered vitamin D signaling is associated with cardiac dysfunction, but the pathogenic mechanism is not clearly understood. We examine the mechanism and the role of vitamin D signaling in the development of cardiac dysfunction. METHODS AND RESULTS: We analyzed 1α-hydroxylase (1α-OHase) knockout (1α-OHase-/-) mice, which lack 1α-OH enzymes that convert the inactive form to hormonally active form of vitamin D. 1α-OHase-/- mice showed modest cardiac hypertrophy at baseline. Induction of pressure overload by transverse aortic constriction (TAC) demonstrated exaggerated cardiac dysfunction in 1α-OHase-/- mice compared to their WT littermates with a significant increase in fibrosis and expression of inflammatory cytokines. Analysis of calcium (Ca2+) transient demonstrated profound Ca2+ handling abnormalities in 1α-OHase-/- mouse cardiomyocytes (CMs), and treatment with paricalcitol (PC), an activated vitamin D3 analog, significantly attenuated defective Ca2+ handling in 1α-OHase-/- CMs. We further delineated the effect of vitamin D deficiency condition to TAC by first correcting the vitamin D deficiency in 1α-OHase-/- mice, followed then by either a daily maintenance dose of vitamin D or vehicle (to achieve vitamin D deficiency) at the time of sham or TAC. In mice treated with vitamin D, there was a significant attenuation of TAC-induced cardiac hypertrophy, interstitial fibrosis, inflammatory markers, Ca2+ handling abnormalities and cardiac function compared to the vehicle treated animals. CONCLUSIONS: Our results provide insight into the mechanism of cardiac dysfunction, which is associated with severely defective Ca2+ handling and defective vitamin D signaling in 1α-OHase-/- mice.

Therapeutic use of H2O2-responsive anti-oxidant polymer nanoparticles for doxorubicin-induced cardiomyopathy.

Doxorubicin (DOX) is a commonly used anti-neoplastic agent but its clinical use is limited due to serious hepatic and cardiac side effects. DOX-induced toxicity is mainly associated with overproduction of reactive species oxygen (ROS) such as hydrogen peroxide (H2O2). We have recently developed H2O2-responsive anti-oxidant polymer, polyoxalate containing vanillyl alcohol (PVAX), which is designed to rapidly scavenge H2O2 and release vanillyl alcohol with anti-oxidant, anti-inflammatory and anti-apoptotic properties. In this study, we report that PVAX nanoparticles are novel therapeutic agents for treating DOX-induced cardiac and hepatic toxicity. Intraperitoneal injection of PVAX nanoparticles (4 mg/kg/day) resulted in significant inhibition in apoptosis in liver and heart of DOX-treated mice by suppressing the activation of poly (ADP ribose) polymerase 1 (PARP-1) and caspase-3. PVAX treatment also prevented DOX-induced cardiac dysfunction. Furthermore, survival rate (vehicle = 35% vs. PVAX = 75%; p < 0.05) was significantly improved in a PVAX nanoparticles-treated group compared with vehicle treated groups. Taken together, we anticipate that PVAX nanoparticles could be a highly specific and potent treatment modality in DOX-induced cardiac and hepatic toxicity.