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Technology in Cancer Research &... 2021To investigate the efficacy of a formula comprising arsenic trioxide and dimercaprol (BAL-ATO) as a radiosensitizing agent in model mice with pancreatic cancer...
OBJECTIVE
To investigate the efficacy of a formula comprising arsenic trioxide and dimercaprol (BAL-ATO) as a radiosensitizing agent in model mice with pancreatic cancer xenografts.
METHODS
Female BALB/c nude mice bearing SW1990 human pancreatic cancer xenografts were divided into four treatment arms, including control, radiotherapy (RT), BAL-ATO, and RT + BAL-ATO groups. Survival and tumor volume were analyzed. We also assessed apoptosis in tumor samples by live imaging and detected hypoxia by confocal laser microscope observation. We further investigated the mechanisms of BAL-ATO action in RT by detecting affected proteins by western blot and immunohistochemistry assays.
RESULTS
Median survival was significantly longer in the RT + BAL-ATO group (64.5 days) compared with the control (49.5 days), RT (39 days), and BAL-ATO (48 days) groups ( 0.001). RT + BAL-ATO inhibited the growth of tumors in mice by 73% compared with the control group, which was significantly higher than the rate of inhibition following RT alone (59%) ( < 0.01). Further analysis showed an improved microenvironment in terms of hypoxia in tumors treated with BAL-ATO alone or RT + BAL-ATO. Expression of signaling molecules associated with pancreatic cancer stem cells, including CD24, CD44, ALDH1A1, Gli-1, and Nestin, was detected in tumors treated with BAL-ATO alone or in combination with RT.
CONCLUSION
These data suggest that BAL-ATO function as a radiosensitizer in mice with pancreatic cancer xenografts, via mechanisms involving hypoxia reduction and inhibition of signaling pathways associated with pancreatic cancer stem cells. BAL-ATO may thus be a promising radiosensitizing agent in patients with pancreatic cancer.
Topics: Animals; Antineoplastic Agents; Arsenic Trioxide; Biomarkers; Cell Line, Tumor; Cell Proliferation; Dimercaprol; Disease Models, Animal; Drug Combinations; Drug Compounding; Female; Humans; Mice; Pancreatic Neoplasms; Prognosis; Radiation Tolerance; Radiation-Sensitizing Agents; Signal Transduction; Treatment Outcome; Xenograft Model Antitumor Assays
PubMed: 34433326
DOI: 10.1177/15330338211036324 -
Frontiers in Immunology 2021Palearctic vipers are medically significant snakes in the genera , and which occur throughout Europe, Central Asia, Near and Middle East. While the ancestral condition... (Comparative Study)
Comparative Study
Palearctic vipers are medically significant snakes in the genera , and which occur throughout Europe, Central Asia, Near and Middle East. While the ancestral condition is that of a small-bodied, lowland species, extensive diversification has occurred in body size, and niche specialization. Using 27 venom samples and a panel of coagulation assays, we evaluated the relative coagulotoxic potency of Palearctic viper venoms and compared their neutralization by three antivenoms (Insoserp Europe, VIPERFAV and ViperaTAb) and two metalloprotease inhibitors (prinomastat and DMPS). We show that variation in morphology parallels variation in the Factor X activating procoagulant toxicity, with the three convergent evolutions of larger body sizes ( genus, genus, and uniquely within the genus) were each accompanied by a significant increase in procoagulant potency. In contrast, the two convergent evolutions of high altitude specialization (the genus and uniquely within the genus) were each accompanied by a shift away from procoagulant action, with the species being particularly potently anticoagulant. Inoserp Europe and VIPERFAV antivenoms were both effective against a broad range of species, with Inoserp able to neutralize additional species relative to VIPERFAV, reflective of its more complex antivenom immunization mixture. In contrast, ViperaTAb was extremely potent in neutralizing but, reflective of this being a monovalent antivenom, it was not effective against other species. The enzyme inhibitor prinomastat efficiently neutralized the metalloprotease-driven Factor X activation of the procoagulant venoms. In contrast, DMPS (2,3-dimercapto-1-propanesulfonic acid), which as been suggested as another potential treatment option in the absence of antivenom, DMPS failed against all venoms tested. Overall, our results highlight the evolutionary variations within Palearctic vipers and help to inform clinical management of viper envenomation.
Topics: Animals; Antivenins; Blood Coagulation; Blood Coagulation Tests; Evolution, Molecular; Humans; Immunoglobulin Fab Fragments; Matrix Metalloproteinase Inhibitors; Organic Chemicals; Snake Bites; Species Specificity; Time Factors; Unithiol; Viper Venoms; Viperidae
PubMed: 34177943
DOI: 10.3389/fimmu.2021.688802 -
BMC Pharmacology & Toxicology May 2021There are no reports on the incidence of chronic mercury poisoning in a large population in China. This study investigated the epidemiology, clinical manifestations,...
BACKGROUND
There are no reports on the incidence of chronic mercury poisoning in a large population in China. This study investigated the epidemiology, clinical manifestations, treatment, and follow-up of Chinese patients with chronic mercury poisoning.
METHODS
Data for 288 mercury poisoning patients were collected at our hospital from July 2014 to September 2019, including sex, age, admission time, blood mercury content, urine mercury content, creatinine, urinary mercury/creatinine ratio, 24-h urinary protein levels, electromyography (EMG) findings, renal biopsy, and follow-up. Patient characteristics were evaluated by statistical and correlation analyses.
RESULTS
First, mercury poisoning in China mainly occurred through occupational exposure and the inappropriate use of mercury-containing cosmetics and Chinese folk remedies (CFRs). Second, the most common symptoms were nervous system (50.3 %), kidney (16.4 %) and breathing (8.0 %). Mercury poisoning-induced Nephrotic syndrome (NS) and peripheral neuropathy are common long-term complications. The complications of occupational and cosmetics-induced mercury poisoning are consistent with international belief. However, the NS caused by CFRs is mainly membranous nephropathy and the probability of peripheral neuropathy caused by CFRs is higher than other pathogens. Third, follow-up data shows that 13 patients with EMG-confirmed neurological injury, 10 showed full recovery after 38.50 ± 8.03 months. Furthermore, among 18 patients with NS, 15 had normal urine protein and serum albumin levels after 22.67 ± 10.26 months.
CONCLUSIONS
Regulation of skin-lightening cosmetic products, safety surveillance of CFRs, and prevention and control of occupational exposure must be improved to decrease the incidence of mercury poisoning in China.
Topics: Adolescent; Adult; Aged; Anti-Inflammatory Agents; Chelating Agents; Child; Child, Preschool; China; Chronic Disease; Cosmetics; Drugs, Chinese Herbal; Female; Follow-Up Studies; Humans; Male; Mercury; Mercury Poisoning; Middle Aged; Occupational Diseases; Occupational Exposure; Prednisone; Retrospective Studies; Unithiol; Young Adult
PubMed: 33941274
DOI: 10.1186/s40360-021-00493-y -
Translational Neurodegeneration Apr 2021The mechanisms underlying lesions of dopaminergic (DA) neurons, an essential pathology of Parkinson's disease (PD), are largely unknown, although oxidative stress is...
BACKGROUND
The mechanisms underlying lesions of dopaminergic (DA) neurons, an essential pathology of Parkinson's disease (PD), are largely unknown, although oxidative stress is recognized as a key factor. We have previously shown that the pro-oxidative aldehyde acrolein is a critical factor in PD pathology, and that acrolein scavenger hydralazine can reduce the elevated acrolein, mitigate DA neuron death, and alleviate motor deficits in a 6-hydroxydopamine (6-OHDA) rat model. As such, we hypothesize that a structurally distinct acrolein scavenger, dimercaprol (DP), can also offer neuroprotection and behavioral benefits.
METHODS
DP was used to lower the elevated levels of acrolein in the basal ganglia of 6-OHDA rats. The acrolein levels and related pathologies were measured by immunohistochemistry. Locomotor and behavioral effects of 6-OHDA injections and DP treatment were examined using the open field test and rotarod test. Pain was assessed using mechanical allodynia, cold hypersensitivity, and plantar tests. Finally, the effects of DP were assessed in vitro on SK-N-SH dopaminergic cells exposed to acrolein.
RESULTS
DP reduced acrolein and reversed the upregulation of pain-sensing transient receptor potential ankyrin 1 (TRPA1) channels in the substantia nigra, striatum, and cortex. DP also mitigated both motor and sensory deficits typical of PD. In addition, DP lowered acrolein and protected DA-like cells in vitro. Acrolein's ability to upregulate TRPA1 was also verified in vitro using cell lines.
CONCLUSIONS
These results further elucidated the acrolein-mediated pathogenesis and reinforced the critical role of acrolein in PD while providing strong arguments for anti-acrolein treatments as a novel and feasible strategy to combat neurodegeneration in PD. Considering the extensive involvement of acrolein in various nervous system illnesses and beyond, anti-acrolein strategies may have wide applications and broad impacts on human health.
Topics: Acrolein; Animals; Behavior, Animal; Cerebral Cortex; Dimercaprol; Dopaminergic Neurons; Hydroxydopamines; Male; Motor Activity; Neostriatum; Neuroprotective Agents; Pain; Pain Measurement; Parkinson Disease, Secondary; Rats; Rats, Sprague-Dawley; Substantia Nigra; TRPA1 Cation Channel
PubMed: 33910636
DOI: 10.1186/s40035-021-00239-0 -
Journal of Medical Toxicology :... Jul 2021
Topics: Antidotes; Brain Diseases; Dimercaprol; Humans; Lead; Pharmaceutical Preparations; United States
PubMed: 33687652
DOI: 10.1007/s13181-021-00830-x -
Nature Communications Dec 2020Snakebite is a medical emergency causing high mortality and morbidity in rural tropical communities that typically experience delayed access to unaffordable...
Snakebite is a medical emergency causing high mortality and morbidity in rural tropical communities that typically experience delayed access to unaffordable therapeutics. Viperid snakes are responsible for the majority of envenomings, but extensive interspecific variation in venom composition dictates that different antivenom treatments are used in different parts of the world, resulting in clinical and financial snakebite management challenges. Here, we show that a number of repurposed Phase 2-approved small molecules are capable of broadly neutralizing distinct viper venom bioactivities in vitro by inhibiting different enzymatic toxin families. Furthermore, using murine in vivo models of envenoming, we demonstrate that a single dose of a rationally-selected dual inhibitor combination consisting of marimastat and varespladib prevents murine lethality caused by venom from the most medically-important vipers of Africa, South Asia and Central America. Our findings support the translation of combinations of repurposed small molecule-based toxin inhibitors as broad-spectrum therapeutics for snakebite.
Topics: Animals; Antivenins; Asia; Benzamidines; Central America; Dimercaprol; Disease Models, Animal; Drug Combinations; Drug Evaluation, Preclinical; Guanidines; Kaplan-Meier Estimate; Male; Mice; Neutralization Tests; Serine Proteases; Snake Bites; Toxins, Biological; Viper Venoms
PubMed: 33323937
DOI: 10.1038/s41467-020-19981-6 -
Acta Pharmaceutica Sinica. B Oct 2020Repurposing small molecule drugs and drug candidates is considered as a promising approach to revolutionise the treatment of snakebite envenoming. In this study, we...
Repurposing small molecule drugs and drug candidates is considered as a promising approach to revolutionise the treatment of snakebite envenoming. In this study, we investigated the inhibiting effects of the small molecules varespladib (nonspecific phospholipase A inhibitor), marimastat (broad spectrum matrix metalloprotease inhibitor) and dimercaprol (metal ion chelator) against coagulopathic toxins found in Crotalinae (pit vipers) snake venoms. Venoms from , , and were separated by liquid chromatography, followed by nanofractionation and mass spectrometry identification undertaken in parallel. Nanofractions of the venom toxins were then subjected to a high-throughput coagulation assay in the presence of different concentrations of the small molecules under study. Anticoagulant venom toxins were mostly identified as phospholipases A, while procoagulant venom activities were mainly associated with snake venom metalloproteinases and snake venom serine proteases. Varespladib was found to effectively inhibit most anticoagulant venom effects, and also showed some inhibition against procoagulant toxins. Contrastingly, marimastat and dimercaprol were both effective inhibitors of procoagulant venom activities but showed little inhibitory capability against anticoagulant toxins. The information obtained from this study aids our understanding of the mechanisms of action of toxin inhibitor drug candidates, and highlights their potential as future snakebite treatments.
PubMed: 33163338
DOI: 10.1016/j.apsb.2020.09.005 -
Biomedicines Aug 2020Animal-derived antivenoms are the only specific therapies currently available for the treatment of snake envenoming, but these products have a number of limitations...
Animal-derived antivenoms are the only specific therapies currently available for the treatment of snake envenoming, but these products have a number of limitations associated with their efficacy, safety and affordability for use in tropical snakebite victims. Small molecule drugs and drug candidates are regarded as promising alternatives for filling the critical therapeutic gap between snake envenoming and effective treatment. In this study, by using an advanced analytical technique that combines chromatography, mass spectrometry and bioassaying, we investigated the effect of several small molecule inhibitors that target phospholipase A (varespladib) and snake venom metalloproteinase (marimastat, dimercaprol and DMPS) toxin families on inhibiting the activities of coagulopathic toxins found in snake venoms. The venoms of , , and , which are known for their potent haemotoxicities, were fractionated in high resolution onto 384-well plates using liquid chromatography followed by coagulopathic bioassaying of the obtained fractions. Bioassay activities were correlated to parallel recorded mass spectrometric and proteomics data to assign the venom toxins responsible for coagulopathic activity and assess which of these toxins could be neutralized by the inhibitors under investigation. Our results showed that the phospholipase A-inhibitor varespladib neutralized the vast majority of anticoagulation activities found across all of the tested snake venoms. Of the snake venom metalloproteinase inhibitors, marimastat demonstrated impressive neutralization of the procoagulation activities detected in all of the tested venoms, whereas dimercaprol and DMPS could only partially neutralize these activities at the doses tested. Our results provide additional support for the concept that combinations of small molecules, particularly the combination of varespladib with marimastat, serve as a drug-repurposing opportunity to develop new broad-spectrum inhibitor-based therapies for snakebite envenoming.
PubMed: 32825484
DOI: 10.3390/biomedicines8090297 -
BMC Neurology Jun 2020Even though recent research has achieved significant advancement in the development of therapeutic approaches for Wilson's diseases (WD), the current treatment options...
BACKGROUND
Even though recent research has achieved significant advancement in the development of therapeutic approaches for Wilson's diseases (WD), the current treatment options available for WD are still limited, especially for WD patients with neurological symptoms. This study is intended to compare the therapeutic approaches for WD patients with neurological symptoms receiving either combined sodium 2, 3-dimercapto-1-propane sulfonate (DMPS) and zinc treatment or D-penicillamine (DPA) monotherapy as first-line therapy, and identify the more effective therapeutic approach.
METHODS
The case records of 158 patients diagnosed with neurological WD were retrospectively analyzed. These patients treated with intravenous DMPS + Zinc and in combination with oral zinc as a maintenance therapy (Group 1) or DPA alone (Group 2) for 1 year. During the period of treatment, the neurological symptoms of the patients were assessed using the Global Assessment Scale (GAS) and Barthel index. The key hematological and biochemical parameters of the patients (such as the levels of aminotransferase, serum ceruloplasmin, 24-h urine copper excretion), as well as adverse effects were recorded and analyzed.
RESULTS
Ninety-three patients in Group 1, displayed decreased GAS scores and increased Barthel indexes consistently in comparison with the baseline (P < 0.01). Among them, 82 patients (88.2%) exhibited significant neurological improvement after 1 year, while 8 patients (8.6%) experienced neurological deterioration. Among the 65 patients in Group 2, 37 patients (58.5%) exhibited neurological improvements, while 17 patients (26.2%) experienced neurological deterioration after 1-year follow up. Six patients discontinued their treatment midway due to their exacerbating neurological symptoms. A comprehensive comparison of the effectiveness of the two courses of treatment revealed that patients in group 1 demonstrated a higher improvement ratio (P < 0.01) and lower worsening ratio of the neurological symptoms for the patients (P < 0.01) in comparison to the patients in group 2. Meanwhile, renal function, liver enzyme and blood cell counts remained stabilized in group1.
CONCLUSIONS
This study indicates that the combined therapeutic approach of DPMS and zinc may be a preferred first-line therapy in treating the neurological symptoms of WD, in comparison to the treatment with DPA.
Topics: Adult; Chelating Agents; Drug Therapy, Combination; Female; Hepatolenticular Degeneration; Humans; Male; Penicillamine; Retrospective Studies; Treatment Outcome; Unithiol; Zinc
PubMed: 32593295
DOI: 10.1186/s12883-020-01827-9