[Research progress on chemical constituents and pharmacological activities of small molecule compounds in scorpions].

Scorpions, a group of oldest animals with wide distribution in the world, have a long history of medicinal use. Scorpio, the dried body of Buthus martensii, is a rare animal medicine mainly used for the treatment of liver diseases, spasm, and convulsions in children in China. The venom has been considered as the active substance of scorpions. However, little is known about the small molecules in the venom of scorpions. According to the articles published in recent years, scorpions contain amino acids, fatty acids, steroids, and alkaloids, which endow scorpions with antimicrobial, anticoagulant, metabolism-regulating, and antitumor activities. This paper summarizes the small molecule chemical components and pharmacological activities of scorpions, with a view to providing valuable information for the discovery of new active molecules and the clinical use of scorpions.

Gastric ulcer treated using an elastic traction ring combined with clip: A case report.

BACKGROUND: There is a high annual incidence of acute, nonvariceal upper gastrointestinal bleeding in Chinese adults. Early endoscopic intervention can reduce rates of rebleeding, surgery, and mortality. The metal clip is the most common method for establishing homeostasis; however, it possesses several limitations. In patients with bleeding secondary to large gastric ulcers, the clip will often fail to stop the bleeding. This article highlights the use of an elastic traction ring as a novel hemostatic method for patients with upper gastrointestinal bleeding. CASE SUMMARY: An elderly male presented to the emergency room with complaints of hematemesis and melena. Endoscopic examination revealed an ulcer (Forrest IIa) in the lesser curvature of the gastric antrum. Six tissue clips and one elastic traction ring were inserted into the stomach cavity to suture the ulcer. The patient recovered quickly without postoperative gastrointestinal bleeding. Two months later, the patient's ulcer was significantly healed. CONCLUSION: To our best knowledge, this is the first report to demonstrate the safety and efficacy of elastic traction rings for upper gastrointestinal bleeding. Elastic traction rings should be considered a routine therapeutic modality for patients with upper gastrointestinal bleeds.

PD-1 inhibitor induces myocarditis by reducing regulatory T cells, activating inflammatory responses, promoting myocardial apoptosis and autophagy.

The present study aimed to explore the pathogenesis of autoimmune myocarditis induced by PD-1 inhibitors and their potential therapeutic targets. Mouse models of autoimmune myocarditis induced by PD-1 inhibitor in mouse models of polymyositis were established. The expression level of PD-1 and regulatory T cells (Tregs), CD4, CD8 + T cells, inflammation, apoptosis and autophagy-related factors, including IL-6, TGF-ß, AMA-M2, Fas/FasL, LC3 and p62 were detected in peripheral blood, muscle or myocardium of mice in each group, using ELISA, RT-PCR, Western Blot and immunofluorescence. In addition, HE and TUNEL staining and ultrastructural scanning were performed on the myocardium of mice in each group. Results showed that the expression level of PD-1 in the two myositis groups was significantly lower than that in the control group, and the level of PD-1 was lower in the myocarditis group than that in the polymyositis group. In the myocardium, TGF-ß, p62, and Tregs proportion showed the same expression level trend as PD-1, while CD8, IL-6, IL-10 and LC3 showed the opposite trend. Levels of Fas/FasL were significantly higher in both myositis groups, but were slightly lower in the myocarditis group, as was AMA-M2. Inflammation, apoptosis, and autophagy were observed in both myositis groups, but were more severe in the myocarditis group. In summary, the decreased expression level of PD-1 leads to decreased Tregs level in the myocardium, aggravated inflammatory response, apoptosis and autophagy, which may be the pathological mechanism of myocarditis induced by PD-1 inhibitors.

Cardioprotective effects of melatonin: Focusing on its roles against diabetic cardiomyopathy.

Melatonin is a pineal-produced indole known for its anti-aging, antiapoptotic and antioxidant properties. In past decades, the protective potentials of melatonin for cardiovascular diseases, such as atherosclerosis and myocardial infarction, have been widely revealed, triggering more investigations focused on other cardioprotective effects of melatonin. Recently, the roles of melatonin in diabetic cardiomyopathy (DCM) have attracted increased attention. In this regard, researchers found that melatonin attenuated cardiac fibrosis and hypertrophy, thus interrupting the development of DCM. Retinoid-related orphan receptor α is a key melatonin receptor that contributed to the cardioprotective effect of melatonin in hearts with DCM. For the downstream mechanisms, the inhibition of mammalian STE20-like kinase 1 plays a pivotal role, which exerts antiapoptotic and proautophagic effects, thus enhancing cardiac tolerance in high-glucose conditions. In addition, other signalling mechanisms, such as sirtuin-1/peroxisome proliferator-activated receptor gamma-coactivator alpha and endoplasmic reticulum-related signalling, are also involved in the protective effects of melatonin on cardiomyocytes under diabetic conditions. This review will focus on the protective signalling mechanisms regulated by melatonin and provide a better understanding of the therapeutic applications of melatonin signalling in DCM.

Resveratrol and Diabetic Cardiomyopathy: Focusing on the Protective Signaling Mechanisms.

Diabetic cardiomyopathy (DCM) is a common cardiovascular complication of diabetic mellitus that is characterized by diastolic disorder in the early stage and clinical heart failure in the later stage. Presently, DCM is considered one of the major causes of death in diabetic patients. Resveratrol (RSV), a naturally occurring stilbene, is widely reported as a cardioprotective substance in many heart diseases. Thus far, the specific roles of RSV in DCM prevention and treatment have attracted great attention. Here, we discuss the roles of RSV in DCM by focusing its downstream targets from both in vivo and in vitro studies. Among such targets, Sirtuins 1/3 and AMP-activated kinase have been identified as key mediators that induce cardioprotection during hyperglycemia. In addition, many other signaling molecules (e.g., forkhead box-O3a and extracellular regulated protein kinases) are also regulated in the presence of RSV and exert beneficial effects such as opposing oxidative stress, inflammation, and apoptosis in cardiomyocytes exposed to high-glucose conditions. The beneficial potential of an RSV/stem cell cotherapy is also reviewed as a promising therapeutic strategy for preventing the development of DCM.

Heat shock protein 70: A promising therapeutic target for myocardial ischemia-reperfusion injury.

Acute myocardial infarction is a major cause of death worldwide. The most important therapy for limiting ischemic injury and infarct size is timely and efficient myocardial reperfusion treatment, which may instead induce cardiomyocyte necrosis due to myocardial ischemia-reperfusion (I/R) injury. Heat shock protein 70 (HSP70), a stress-inducible protein, is overexpressed during myocardial I/R. The induced HSP70 is shown to regulate several intracellular proteins (e.g., transcription factors, enzymes, and apoptosis-related proteins) and signaling pathways (e.g., c-Jun N-terminal kinase pathway and extracellular-signal-regulated kinase 1/2 pathway), forming a complicated network that contributes to reducing reactive oxygen species accumulation, improving calcium homeostasis, inhibiting cellular apoptosis, thereby enhancing the stress adaption of myocardium to I/R injury. In addition, the extracellular HSP70, which is released from injured cardiomyocytes during I/R, acts as a proinflammatory mediator that results in cell death, while the intracellular HSP70 exerts antiinflammatory effects by suppressing proinflammatory signaling pathways. Notably, HSP70 is induced and contributes to the cardioprotection in several types of preconditioning and postconditioning. Meanwhile, it is shown that the cardioprotective effectiveness of preconditioning-induced HSP70 (e.g., hyperthermia preconditioning-induced HSP70) can be impaired by certain pathological conditions, such as hyperlipidemia and hyperglycemia. Thus, we highlight the widespread cardioprotective involvement of HSP70 in preconditioning and postconditioning and elucidate how HSP70-mediated cardioprotection is impaired in these pathological conditions. Furthermore, several therapeutic potentials of HSP70 against myocardial I/R injury and potential directions for future studies are also provided in this review.

Mitochondrial Complex V α Subunit Is Critical for Candida albicans Pathogenicity through Modulating Multiple Virulence Properties.

The α subunit (ATP1) is a vital component of mitochondrial complex V which counts for the majority of cellular ATP production in a living organism. Nevertheless, how the α subunit influences other cellular processes such as pathogenicity in Candida albicans remains poorly understood. To address this question, ATP1 mutant (atp1Δ/Δ) and the gene-reconstituted strain (atp1Δ/ATP1) have been constructed in this study and their pathogenicity-related traits are compared to those of wild type (WT). In a murine model of disseminated candidiasis, atp1Δ/Δ infected mice have a significantly higher survival rate and experience a lower fungal burden in tissues. In in vitro studies atp1Δ/Δ lose a capability to damage or destroy macrophages and endothelial cells. Furthermore, atp1Δ/Δ is not able to grow under either glucose-denial conditions or high H2O2 conditions, both of which are associated with the potency of the macrophages to kill C. albicans. Defects in filamentation and biofilm formation may impair the ability of atp1Δ/Δ to penetrate host cells and establish robust colonies in the host tissues. In concert with these pathogenic features, intracellular ATP levels of atp1Δ/Δ can drop to 1/3 of WT level. These results indicate that the α subunit of Complex V play important roles in C. albicans pathogenicity.

Synergistic Effects of Tetrandrine with Posaconazole Against Aspergillus fumigatus.

In our earlier in vitro and in vivo studies, synergistic effects were observed when itraconazole or voriconazole were combined with tetrandrine (TET) against Aspergillus fumigatus, and the synergistic mechanism was related to inhibition of the drug efflux pump. Posaconazole (PCZ) is a broad-spectrum triazole antifungal agent used for the treatment of diverse fungal infections, including aspergillosis and candidiasis. Herein, the antifungal effects of TET are further investigated in vitro and in vivo alone or combined with PCZ against 20 clinical isolates of A. fumigatus. We found that the minimal inhibitory concentrations (MICs) of PCZ were decreased one- to twofold and three- to fivefold across a series of concentration gradients in vitro in presence of TET. Time-killing curves revealed that the synergy was dependent on TET and PCZ concentrations as well as incubation time. The combination could further downregulate the expression of MDR2, MDR3, MDR4, and ATRF in PCZ-resistant strain, however, it has subtle effects on TET-synergized mechanism. In addition, TET in combination with PCZ significantly prolonged mice survival time and reduced kidney and brain tissue burdens in vivo. Our data in vitro and in vivo demonstrate that TET is an effective synergist with azoles against A. fumigates.

Acute and sub-chronic toxicity of tetrandrine in intravenously exposed female BALB/c mice.

OBJECTIVE: To evaluate the acute and sub-chronic toxicity of intravenously administered tetrandrine (TET) in female BALB/c mice. METHODS: The median lethal dose (LD50) of intravenously administered TET was calculated in mice using Dixon's up-and-down method. In the acute toxicity study, mice were intravenously administered with TET at a single dose of 20, 100, 180, 260 and 340 mg/kg, respectively and were evaluated at 14 days after administration. In the sub-acute toxicity study, mice were intravenously administered various doses of TET (30, 90 and 150 mg/kg) each day for 14 consecutive days. Clinical symptoms, mortality, body weight, serum biochemistry, organ weight and histopathology were examined at the end of the experiment, as well as after a 1-week recovery period. RESULT: LD50 was found to be 444.67±35.76 mg/kg. In the acute toxicity study, no statistically signifificant differences in body weight, blood biochemistry, or organ histology were observed between the administration and control groups when mice were intravenously administered with single dose at 20, 100, 180, 260 and 340 mg/kg of TET (P >0.05). In the sub-acute toxicity study, no signifificant changes in body weight, biochemistry and organ histology were observed with up to 90 mg/kg of TET compared with the control group (P >0.05), however, in the 150 mg/kg administered group, TET induced transient toxicity to liver, lungs and kidneys, but withdrawal of TET can lead to reversal of the pathological conditions. CONCLUSIONS: The overall fifindings of this study indicate that TET is relatively non-toxic from a single dose of 20, 100, 180, 260 or 340 mg/kg, and that up to 90 mg/kg daily for 14 consecutive days can be considered a safe application dose.

An in vitro and in vivo study on the synergistic effect and mechanism of itraconazole or voriconazole alone and in combination with tetrandrine against Aspergillus fumigatus.

In this study, we investigated the in vitro antifungal effects of itraconazole/voriconazole (ITR/VRC) alone and in combination with tetrandrine (TET) against 23 clinical isolates of A. fumigatus using a chequerboard microdilution method. The dynamic antifungal effects of TET with ITR/VRC against A. fumigatus were assessed in vivo using time-kill curves following systemic infection of mice with A. fumigatus. After treatment, efflux pump activity was determined by the efflux of rhodamine 6G (R6G). When ITR was combined with TET, ITR MICs were reduced from 0.125-32 to 0.0625-2 µg ml(-1), and TET MICs were reduced from 256-512 to 8-64 µg ml(-1). When VRC was combined with TET, VRC MICs were reduced from 0.125-2 to 0.03125-0.5 µg ml(-1), and TET MICs were reduced from 256-512 to 8-256 µg ml(-1). Time-kill curves revealed that A. fumigatus viability was reduced after treatment with ITR/VRC combined with TET versus ITR/VRC alone. ITR/VRC combined with TET significantly prolonged mouse survival and reduced kidney and brain tissue burdens versus ITR/VRC alone (P < 0.05). Moreover, TET inhibited R6G efflux of A. fumigatus. Thus, in vitro and in vivo, TET acted synergistically with ITR/VRC against A. fumigatus, and the synergistic mechanism was related to inhibition of the drug efflux pump.

Synergistic mechanism for tetrandrine on fluconazole against Candida albicans through the mitochondrial aerobic respiratory metabolism pathway.

We found that tetrandrine (TET) can reverse the resistance of Candida albicans to fluconazole (FLC) and that this interaction is associated with the inhibition of drug efflux pumps. Mitochondrial aerobic respiration, which plays a major role in C. albicans metabolism, is the primary source of ATP for cellular processes, including the activation of efflux pumps. However, it was unclear if TET exerts its synergistic action against C. albicans via its impact on the mitochondrial aerobic respiratory metabolism. To investigate this mechanism, we examined the impact of FLC in the presence or absence of TET on two C. albicans strains obtained from a single parental source (FLC-sensitive strain CA-1 and FLC-resistant strain CA-16). We analysed key measures of energy generation and conversion, including the activity of respiration chain complexes I and III (CI and CIII), ATP synthase (CV) activity, and the generation of reactive oxygen species (ROS), and studied intracellular ATP levels and the mitochondrial membrane potential (ΔΨm), which has a critical impact on energy transport. Mitochondrial morphology was observed by confocal microscopy. Our functional analyses revealed that, compared with strains treated only with FLC, TET+FLC increased the ATP levels and decreased ΔΨm in CA-1, but decreased ATP levels and increased ΔΨm in CA-16 (P<0.05). Additionally, CI, CIII and CV activity decreased by 23-48%. The production of ROS increased by two- to threefold and mitochondrial morphology was altered in both strains. Our data suggested that TET impacted mitochondrial aerobic respiratory metabolism by influencing the generation and transport of ATP, reducing the utilization of ATP, and resulting in the inhibition of drug efflux pump activity. This activity contributed to the synergistic action of TET on FLC against C. albicans.

Alcohol dehydrogenase I expression correlates with CDR1, CDR2 and FLU1 expression in Candida albicans from patients with vulvovaginal candidiasis.

BACKGROUND: The most critical mechanism governing drug resistance in Candida albicans (C. albicans) involves efflux pumps, the functionality of which largely depends on energy metabolism. Alcohol dehydrogenase I (ADH1) plays an important role in intracellular energy metabolism. The aim of this study was to explore the relationship between ADH1 and drug resistance in C. albicans. METHODS: Twenty clinical C. albicans samples isolated from individual patients diagnosed with vulvovaginal candidiasis, and two C. albicans strains obtained from a single parental source (the fuconazole (FLC)-sensitive strain CA-1S and the FLC-resistant strain CA-16(R)) were included in our study. In accordance with the Clinical and Laboratory Standards Institute (CLSI) M27-A3 guidelines, we used the microdilution method to examine the FLC minimum inhibitory concentrations (MICs) and real-time reverse transcription polymerase chain reaction (RT-PCR) to measure the mRNA expression levels of ADH1 and the azole resistance genes CDR1, CDR2, MDR1, FLU1 and ERG11 in all the isolates. RESULTS: A highly significant positive correlation between the mRNA levels of ADH1 and the MICs (rs = 0.921, P = 0.000), as well as positive correlations between the mRNA level of ADH1 and those of CDR1, CDR2 and FLU1 (rs of 0.704, 0.772 and 0.779, respectively, P < 0.01), were observed in the 20 clinical C. albicans samples. The relative expression of ADH1 was upregulated 10.63- to 17.61-fold in all of the drug-resistant isolates. No correlations were found between the mRNA levels of ADH1 and those of MDR1 or ERG11 (P > 0.05). The mRNA levels of the examined drug resistance genes were higher in the CA-16(R) strain than in CA-1(S), and the mRNA levels of ADH1 in CA-16(R) were 11.64-fold higher than those in CA-1(S) (P < 0.05). CONCLUSIONS: These results suggest that high levels of ADH1 transcription are implicated in FLC resistance in C. albicans and that the mRNA expression levels of ADH1 are positively correlated with those of CDR1, CDR2 and FLU1.

Proteomic analysis reveals that Adh1p is involved in a synergistic fluconazole and tetrandrine mechanism against Candida albicans.

We previously showed that Adh1p participates in fluconazole (FLC) resistance in Candida albicans through a mechanism that may involve efflux pumps. We also found that the concomitant use of tetrandrine (TET) and FLC provided a synergistic action against C. albicans and that the mechanism of action could be related to inhibition of a drug efflux system. To determine whether Adh1p participates in the synergistic antifungal activity of TET against C. albicans, we performed a comparative proteomic study comparing cells treated with FLC and/or TET in FLC-sensitive CA-3 and untreated control cells. Proteins were analyzed using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), and differentially expressed proteins were identified through matrix-assisted laser desorption/ionization time-of-flight (MALDI TOF/TOF) mass spectrometry. The resulting data were searched against a C. albicans protein database. Our analyses identified six differentially expressed proteins; four (Eno1p, Adh1p, Slb1p, and Tdh1p) were down-regulated, and two (Xyl2p, and Cdc19p) were up-regulated. The Adh1p mRNA levels were consistent with the Adh1p protein levels in all of the groups. The results suggest that Adh1p participates in the synergistic antifungal activity of TET against C. albicans.

In vivo studies of pharmacokinetics and efficacy of Bismuth-213 labeled antimelanoma monoclonal antibody 9.2.27.

OBJECTIVES: Key objectives of the study were to determine the pharmacokinetics and efficacy of the alpha emitting Bismuth-213 labeled 9.2.27 alpha-immunoconjugate (AIC). METHODS: Balb/c nude mice were injected with varying doses of AIC to determine the pharmacokinetics of the AIC. The results were normalized to percent counts per minute (CPM) per gram per 3.7 MBq of the AIC (%CPM/g/3.7MBq) for each organ. Efficacy was determined by injected varying doses of AIC to different stages of tumor growth for intra-lesional, systemic and multiple dose TAT. RESULTS: Biodistribution studies showed similar pharmacokinetics for blood and brain, liver, kidneys, spleen, gut, heart, lungs and bone marrow, indicating that there was no retention of AIC. This is particularly important for brain (due to the presence of NG2+ cells) as the antibody 9.2.27 may reach NG2 positive cells. Tumor growth at 2-days post-inoculation was completely inhibited by TAT. The response to TAT was inversely proportional to tumor growth, i.e., a reduction in response was observed with increased tumor burden. A multiple dose regime was found to be more effective than single dose. CONCLUSIONS: TAT is effective for the treatment of micrometastatic melanoma, when the tumor is preangiogenic in the form of isolated cells or cell clusters. There is no evidence of retention of AIC in brain, kidneys and other vital organs.