The Application Methods of Mitogen-activated Protein Kinase Signal Pathway Inhibitors SP600125 and SB203580 in Long-term in Vivo Experiments / Métodos de aplicación de los inhibidores SP600125 y SB203580 de la vía de señalización de la proteína quinasa activada por mitógeno en experimentos in vivo a largo plazo

ABSTRACT Objective: To explore the application methods of mitogen-activated protein kinase signal pathway inhibitors SP600125 and SB203580 in long-term in vivo experiments. Methods: A total of 55 healthy New Zealand rabbits were randomly divided into blank control group, model control group, SP low dose group, SP high dose group, SP blank group, SB low dose group, SB high dose group, SB blank group, dimethyl sulfoxide (DMSO) control group, DMSO blank group, and positive control group. Since the first day of the experiment, each group was administered the corresponding treatment for four weeks continuously. Then, the myocardial c-Jun N-terminal kinase (JNK) and the total protein of p38, protein phosphorylation and its gene expression levels were detected. Results: After intravenous treatment with adriamycin, the myocardial phosphorylate-JNK (p-JNK) and phosphorylate-p38 (p-p38) levels in all groups were increased to varying degrees, of which the model control group increased the most significantly (p < 0.05). Compared with the model control group, the myocardial p-JNK and p-p38 increased more slowly in the SP low dose group, SP high dose group, SB low dose group, SB high dose group and positive control group (p < 0.05), of which the increase in the SP high dose group and the SB high dose group was the slowest (p < 0.05). After four weeks, the total protein and messenger ribonucleic acid of the myocardial JNK and p38 in all groups had no statistically significant difference (p > 0.05). Conclusion: The continuous intravenous injection of SP600125 and SB203580 for four weeks significantly reduced the protein phosphorylation levels of JNK and p38, which provides a practical avenue for the long-term study in vivo.

RESUMEN Objetivo: Explorar los métodos de aplicación de los inhibidores SP600125 y SB203580 de la vía de señalización de la proteína quinasa activada por mitógeno en experimentos in vivo a largo plazo. Métodos: Un total de 55 conejos sanos de Nueva Zelandia fueron divididos aleatoriamente en los grupos siguientes: grupo de control en blanco, grupo de control modelo, grupo de dosis baja SP, grupo de dosis alta SP, grupo en blanco SP, grupo de dosis baja SB, grupo de dosis alta SB, grupo en blanco SB, grupo de control dimetilsulfóxido (DMSO), grupo en blanco DMSO, y grupo de control positivo. Desde el primer día del experimento, a cada grupo se le administró el tratamiento correspondiente por cuatro semanas continuas. Entonces, se detectaron la quinasa c-Jun N-terminal (JNK) miocárdica y la proteína p38 total, así como la fosforilación proteica y sus niveles de expresión génica. Resultados: Después del tratamiento intravenoso con adriamicina, los niveles de fosfo-JNK (p-JNK) y fosfo-p38 (p-p38) del miocardio aumentaron en todos los grupos en diversos grados, siendo el aumento del grupo de control modelo el más significativo (p < 0.05). En comparación con el grupo de control modelo, p-JNK y p-p38 miocárdicos aumentaron más lentamente en el grupo de dosis baja SP, el grupo de dosis alta SP, el grupo de dosis baja SB, el grupo de dosis alta SB, y el grupo de control positivo (p < 0.05). De estos, el aumento en el grupo de dosis alta SP y el grupo de dosis alta SB fue el más lento (p < 0.05). Después de cuatro semanas, la proteína total y el ácido ribonucleico mensajero de JNK y p38 miocárdicos en todos los grupos, no tuvieron diferencias significativas (p > 0.05). Conclusión: La inyección intravenosa continua de SP600125 y SB203580 durante cuatro semanas redujo significativamente los niveles de fosforilación proteica de JNK y p38, lo que proporciona una vía práctica para el estudio a largo plazo in vivo.

Macelignan inhibits bee pathogenic fungi Ascophaera apis growth through HOG1 pathway

Ascosphaera apis is a bee pathogen that causes bee larvae infection disease, to which treatment is not yet well investigated. The aim of this study was to investigate antifungal susceptibility in vitro against A. apis and to identify a new antifungal agent for this pathogen through minimal inhibitory concentration (MIC) assay and western blot analysis. Macelignan had 1.56 and 3.125 μg/mL MIC against A. apis after 24 and 48 h, respectively, exhibiting the strongest growth inhibition against A. apis among the tested compounds (corosolic acid, dehydrocostus lactone, loganic acid, tracheloside, fangchinoline and emodin-8-O-β-D-glucopyranoside). Furthermore, macelignan showed a narrow-ranged spectrum against various fungal strains without any mammalian cell cytotoxicity. In spite of miconazole having powerful broad-ranged anti-fungal activity including A. apis, it demonstrated strong cytotoxicity. Therefore, even if macelignan alone was effective as an antifungal agent to treat A. apis, combined treatment with miconazole was more useful to overcome toxicity, drug resistance occurrence and cost effectiveness. Finally, HOG1 was revealed as a target molecule of macelignan in the anti-A. apis activity by inhibiting phosphorylation using S. cerevisiae as a model system. Based on our results, macelignan, a food-grade antimicrobial compound, would be an effective antifungal agent against A. apis infection in bees.

Anticancer properties and enhancement of therapeutic potential of cisplatin by leaf extract of Zanthoxylum armatum DC

BACKGROUND: Clinical use of chemotherapeutic drug, cisplatin is limited by its toxicity and drug resistance. Therefore, efforts continue for the discovery of novel combination therapies with cisplatin, to increase efficacy and reduce its toxicity. Here, we screened 16 medicinal plant extracts from Northeast part of India and found that leaf extract of Zanthoxylum armatum DC. (ZALE) induced cytotoxicity as well as an effect on the increasing of the efficiency of chemotherapeutic drugs (cisplatin, mitomycin C and camptothecin). This work shows detail molecular mechanism of anti-cancer activity of ZALE and its potential for combined treatment regimens to enhance the apoptotic response of chemotherapeutic drugs. RESULTS: ZALE induced cytotoxicity, nuclear blebbing and DNA fragmentation in HeLA cells suggesting apoptosis induction in human cervical cell line. However, the apoptosis induced was independent of caspase 3 activation and poly ADP ribose polymerase (PARP) cleavage. Further, ZALE activated Mitogen-activated protein kinases (MAPK) pathway as revealed by increased phosphorylation of extracellular-signal-regulated kinases (ERK), p38 and c-Jun N-ter-minal kinase (JNK). Inhibition of ERK activation but not p38 or JNK completely blocked the ZALE induced apoptosis suggesting an ERK dependent apoptosis. Moreover, ZALE generated DNA double strand breaks as suggested by the induction γH2AX foci formation. Interestingly, pretreatment of certain cancer cell lines with ZALE, sensitized the cancer cells to cisplatin and other chemotherapeutic drugs. Enhanced caspase activation was observed in the synergistic interaction among chemotherapeutic drugs and ZALE. CONCLUSION: Purification and identification of the bio-active molecules from the ZALE or as a complementary treatment for a sequential treatment of ZALE with chemotherapeutic drugs might be a new challenger to open a new therapeutic window for the novel anti-cancer treatment.

Effects of Er-Miao-San extracts on TNF-alpha-indueed MMP-1 expression in human dermal fibroblasts

BACKGROUND: Various health benefits have been attributed to Er-Miao-San (EMS), a traditional Chinese herbal formulation that contains equal amounts of cortex phellodendri (Phellodendron amurense Ruprecht) and rhizoma atractylodis (Atractylodes lancea D.C). However, its effect on the anti-inflammatory activity in human dermal fibroblasts (HDFs) and the mechanism underlying this effect are unknown. RESULTS: This study investigated the effects of EMS on TNF-α-induced MMP-1 expression in HDFs. Our data show that EMS inhibited TNF-α-induced MMP-1 expression in a concentration-dependent manner. Interestingly, EMS maintained IkB content without inhibiting the phosphorylation of MAPKs, which are well-established upstream kinases of NF-kB. Moreover, EMS reduced the level of nuclear p65 protein in HDFs. Luciferase assay revealed that EMS inhibits the transcriptional activity of NF-kBbystabilizing IkB. Our results show that EMS exerts its anti-inflammatory effect by inhibiting NF-kB-regulated genes such as IL-1ß and IL-8. Moreover, EMS effectively inhibited TNF-α-induced expression of MMP-1 via the NF-kBpathway. CONCLUSIONS: Taken together, our data suggest that EMS could potentially be used as an anti-inflammatory and anti-aging treatment.

Nefrotoxicidade aguda da cisplatina: mecanismos moleculares / Acute nephrotoxicity of cisplatin: molecular mechanisms

As drogas nefrotóxicas são responsáveis por aproximadamente 20% dos episódios de IRA em pacientes internados e ambulatoriais. A nefrotoxicidade pela cisplatina é um dos principais fatores limitantes em até 20% dos pacientes que recebem a droga, ocasionando lesões em células do epitélio tubular renal. A toxicidade da cisplatina é determinada pelo tecido-alvo e acúmulo nas células, além da interação com diversas estruturas subcelulares e com macromoléculas. A cisplatina se acumula e interfere com o funcionamento de diferentes organelas, tais como: mitocôndrias, lisossomas, retículo endoplasmático, núcleo e membrana celular, gerando inflamação e morte celular. Esta revisão tem como objetivo definir as bases fisiopatológicas e bioquímicas da nefrotoxicidade da cisplatina, revisando os principais mecanismos moleculares que levam à toxicidade tubular da cisplatina.

The nephrotoxic drugs have been responsible for about 20% of AKI episodes in inpatients and outpatients. The cisplatin nephrotoxicity is a major limiting factors in 20% of patients who have received the drug, triggering injuries in renal tubular epithelialcells. Cisplatin toxicity is determined by the target tissue and cells accumulation besides the interaction with various subcellular structures and macromolecules. Cisplatin accumulates and interferes with the functioning of different organelles such as mitochondria, lysosomes, endoplasmic reticulum, nuclei and cell membranes, causing inflammation and cell death. This review aims to define the pathophysiology and biochemistry of the cisplatin nephrotoxicity, reviewing the main molecular mechanisms that lead to tubular cisplatin toxicity.

Roles of mitogen-activated protein kinases and angiotensin II in renal development

Experimental and clinical evidence suggests that angiotensin II (AII) participates in renal development. Renal AII content is several-fold higher in newborn rats and mice than in adult animals. AII receptors are also expressed in higher amounts in the kidneys of newborn rats. The kidneys of fetuses whose mother received a type 1 AII receptor (AT1) antagonist during gestation present several morphological alterations. Mutations in genes that encode components of the renin-angiotensin system are associated with autosomal recessive renal tubular dysgenesis. Morphological changes were detected in the kidneys of 3-week-old angiotensin-deficient mice. Mitogen-activated protein kinases (MAPKs) are important mediators that transduce extracellular stimuli to intracellular responses. The MAPK family comprises three major subgroups, namely extracellular signal-regulated protein kinase (ERK), c-jun N-terminal kinases (JNK), and p38 MAPK (p38). Important events in renal growth during nephrogenesis such as cellular proliferation and differentiation accompanied by apoptosis on a large scale can be mediated by MAPK pathways. A decrease in glomerulus number was observed in embryos cultured for 48 and 120 h with ERK or p38 inhibitors. Many effects of AII are mediated by MAPK pathways. Treatment with losartan during lactation provoked changes in renal function and structure associated with alterations in AT1 and type 2 AII (AT2) receptors and p-JNK and p-p38 expression in the kidney. Several studies have shown that AII and MAPKs play an important role in renal development. However, the relationship between the effects of AII and MAPK activation on renal development is still unclear.

In vitro anti-proliferation/cytotoxic activity of cantharidin (Spanish Fly) and related derivatives

The anti-cancer therapeutic promise of cantharidin is limited because of its high mammalian toxicity. In order to find new anti-cancer lead compounds with reduced toxicity of the cantharidin prototype, the following seven derivatives were screened against the human SH-SY5Y neuroblastoma and MCF-7 breast cancer cells in vitro: 2,3-dimethyl-7-oxabicylo-[2.2.1]heptane-2,3-dicarboxylic anhydride (cantharidin) [1], 1-cyclohexen-1,2-dicarboxylic anhydride [2], cis-4-cyclohexen-1,2-dicarboxylic anhydride [3], cis-1, 2-cyclohexanedicarboxylic anhydride [4], exo-7-oxabicyclo[2.2.1]hept-5-ene-2-3 dicarboxylic anhydride [5], exo-7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride (norcantharidin) [6], and (S)-(-)-O-acetylmalic anhydride [7]. Cantharidin, was found to be the most effective anti-proliferative compound on both cell lines. However, on the human neuroblastoma cells cantharidin was of equal toxicity to compound [6]. Mode of action studies revealed that cantharidin inhibited growth factor-mediated activation of mitogen activated protein kinase (MAPkinase) and attenuated the de-phosphorylation of the extracellular regulated kinases 1 and 2 (erk1 and erk2)