Mefloquine Is Active In Vitro and In Vivo againstMycobacterium avium Complex

ABSTRACT Despite the development of several agents, new classes of antimicrobials with activity against the Mycobacterium avium complex (MAC) are needed. Based on a broad screening of compounds, we found that mefloquine has MICs of 8 to 16 μg/ml by the BACTEC system and 16 μg/ml by broth microdilution for five MAC strains tested. An expansion of the screening with broth microdilution to 24 macrolide-susceptible strains and 6 macrolide-resistant strains determined that the MIC for all strains was 16 μg/ml. To determine the intracellular activity of mefloquine, U937 macrophage monolayers infected with MAC strain 101, 100, or 109 (serovars 1, 8, and 4) were treated with mefloquine daily, and the number of intracellular bacteria was quantitated after 4 days. Significant growth inhibition against the three MAC strains at concentrations greater than or equal to 10 μg/ml (P < 0.05) was obtained. Due to the encouraging anti-MAC activity, in vivo efficacy in beige mice infected with MAC 101 was evaluated. Animals were treated with 5, 10, 20, or 40 mg/kg of body weight daily, three times a week, twice a week, or once a week for 4 weeks, and bacteria were quantitated in blood, liver, and spleen. No toxicity was observed with any of the treatment regimens. Mefloquine had borderline bactericidal activity at a dosage of 40 mg/kg daily (100% inhibition compared with a 1-week control), and significant inhibition was obtained at dosages of 40 mg/kg three times a week, as well as 20 mg/kg daily. Mefloquine had no significant effect on bacteremia. A combination of mefloquine and ethambutol showed significantly more activity than did either drug alone in liver, spleen, and blood; the combination was also bactericidal againstM. avium. Although safety is a potential concern, mefloquine and related compounds deserve further investigation as anti-MAC therapies.

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The Development of Homologous (Canine/Anti-Canine) Antibodies in Dogs with Haemophilia A (Factor VIII Deficiency): A Ten-Year Longitudinal Study

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651541 ◽

1993 ◽

Vol 69 (01) ◽

pp. 021-024 ◽

Cited By ~ 20

Author(s):

Shawn Tinlin ◽

Sandra Webster ◽

Alan R Giles

Keyword(s):

Factor Viii ◽

Canine Model ◽

Significant Inhibition ◽

Human Condition ◽

Haemophilia A ◽

Variable Expression ◽

The Family ◽

Over Time

SummaryThe development of inhibitors to factor VIII in patients with haemophilia A remains as a serious complication of replacement therapy. An apparently analogous condition has been described in a canine model of haemophilia A (Giles et al., Blood 1984; 63:451). These animals and their relatives have now been followed for 10 years. The observation that the propensity for inhibitor development was not related to the ancestral factor VIII gene has been confirmed by the demonstration of vertical transmission through three generations of the segment of the family related to a normal (non-carrier) female that was introduced for breeding purposes. Haemophilic animals unrelated to this animal have not developed functionally significant factor VIII inhibitors despite intensive factor VIII replacement. Two animals have shown occasional laboratory evidence of factor VIII inhibition but this has not been translated into clinical significant inhibition in vivo as assessed by clinical response and F.VIII recovery and survival characteristics. Substantial heterogeneity of inhibitor expression both in vitro and in vivo has been observed between animals and in individual animals over time. Spontaneous loss of inhibitors has been observed without any therapies designed to induce tolerance, etc., being instituted. There is also phenotypic evidence of polyclonality of the immune response with variable expression over time in a given animal. These observations may have relevance to the human condition both in determining the pathogenetic factors involved in this condition and in highlighting the heterogeneity of its expression which suggests the need for caution in the interpretation of the outcome of interventions designed to modulate inhibitor activity.

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Репрограммированые in vitro на М3 фенотип макрофаги останавливают рост солидной карциномы in vivo

ZHurnal «Patologicheskaia fiziologiia i eksperimental`naia terapiia» ◽

10.25557/0031-2991.2018.01.41-46 ◽

2018 ◽

pp. 41-46

Author(s):

А.А. Раецкая ◽

С.В. Калиш ◽

С.В. Лямина ◽

Е.В. Малышева ◽

О.П. Буданова ◽

...

Keyword(s):

Solid Tumor ◽

Antitumor Effect ◽

Tumor Development ◽

Significant Inhibition ◽

The Body ◽

Ehrlich Carcinoma ◽

Solid Carcinoma ◽

Ec Cells

Цель исследования. Доказательство гипотезы, что репрограммированные in vitro на М3 фенотип макрофаги при введении в организм будут существенно ограничивать развитие солидной карциномы in vivo . Методика. Рост солидной опухоли инициировали у мышей in vivo путем подкожной инъекции клеток карциномы Эрлиха (КЭ). Инъекцию макрофагов с нативным М0 фенотипом и с репрограммированным M3 фенотипом проводили в область формирования солидной КЭ. Репрограммирование проводили с помощью низких доз сыворотки, блокаторов факторов транскрипции STAT3/6 и SMAD3 и липополисахарида. Использовали две схемы введения макрофагов: раннее и позднее. При раннем введении макрофаги вводили на 1-е, 5-е, 10-е и 15-е сут. после инъекции клеток КЭ путем обкалывания макрофагами с четырех сторон область развития опухоли. При позднем введении, макрофаги вводили на 10-е, 15-е, 20-е и 25-е сут. Через 15 и 30 сут. после введения клеток КЭ солидную опухоль иссекали и измеряли ее объем. Эффект введения макрофагов оценивали качественно по визуальной и пальпаторной характеристикам солидной опухоли и количественно по изменению ее объема по сравнению с группой без введения макрофагов (контроль). Результаты. Установлено, что M3 макрофаги при раннем введении от начала развития опухоли оказывают выраженный антиопухолевый эффект in vivo , который был существенно более выражен, чем при позднем введении макрофагов. Заключение. Установлено, что введение репрограммированных макрофагов M3 ограничивает развитие солидной карциномы в экспериментах in vivo . Противоопухолевый эффект более выражен при раннем введении М3 макрофагов. Обнаруженные в работе факты делают перспективным разработку клинической версии биотехнологии ограничения роста опухоли, путем предварительного программирования антиопухолевого врожденного иммунного ответа «в пробирке». Aim. To verify a hypothesis that macrophages reprogrammed in vitro to the M3 phenotype and injected into the body substantially restrict the development of solid carcinoma in vivo . Methods. Growth of a solid tumor was initiated in mice in vivo with a subcutaneous injection of Ehrlich carcinoma (EC) cells. Macrophages with a native M0 phenotype or reprogrammed towards the M3 phenotype were injected into the region of developing solid EC. Reprogramming was performed using low doses of serum, STAT3/6 and SMAD3 transcription factor blockers, and lipopolysaccharide. Two schemes of macrophage administration were used: early and late. With the early administration, macrophages were injected on days 1, 5, 10, and 15 following the injection of EC cells at four sides of the tumor development area. With the late administration, macrophages were injected on days 10, 15, 20, and 25. At 15 and 30 days after the EC cell injection, the solid tumor was excised and its volume was measured. The effect of macrophage administration was assessed both qualitatively by visual and palpation characteristics of solid tumor and quantitatively by changes in the tumor volume compared with the group without the macrophage treatment. Results. M3 macrophages administered early after the onset of tumor development exerted a pronounced antitumor effect in vivo , which was significantly greater than the antitumor effect of the late administration of M3 macrophages. Conclusion. The observed significant inhibition of in vivo growth of solid carcinoma by M3 macrophages makes promising the development of a clinical version of the biotechnology for restriction of tumor growth by in vitro pre-programming of the antitumor, innate immune response.

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Peculiarities of the course of type I allergic reactions in patients with blood diseases

Terapevt (General Physician) ◽

10.33920/med-12-2004-06 ◽

2020 ◽

pp. 40-50

Author(s):

A. Nikitina

Keyword(s):

Search Engines ◽

Anaphylactic Shock ◽

Type I ◽

Allergic Reactions ◽

Common Cause ◽

Blood Diseases ◽

Treatment Regimens ◽

Modern Methods

Analysis of literature data presented in search engines — Elibrary, PubMed, Cochrane — concerning the risk of developing type I allergic reactions in patients with blood diseases is presented. It is shown that the most common cause of type I allergic reactions is drugs included in the treatment regimens of this category of patients. The article presents statistics on the increase in the number of drug allergies leading to cases of anaphylactic shock in patients with blood diseases. Modern methods for the diagnosis of type I allergic reactions in vivo and in vitro are considered.

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ANTITUMOR EFFECT OF COLLOIDAL SILVER BISILICATE IN EXPERIMENTAL IN VITRO AND IN VIVO STUDIES

Problems in oncology ◽

10.37469/0507-3758-2019-65-5-760-765 ◽

2019 ◽

Vol 65 (5) ◽

pp. 760-765

Author(s):

Margarita Tyndyk ◽

Irina Popovich ◽

A. Malek ◽

R. Samsonov ◽

N. Germanov ◽

...

Keyword(s):

Antitumor Activity ◽

Tumor Growth ◽

Tumor Cells ◽

Human Tumor ◽

Significant Inhibition ◽

In Vivo Studies ◽

Ehrlich Carcinoma ◽

In Vivo Experiments

The paper presents the results of the research on the antitumor activity of a new drug - atomic clusters of silver (ACS), the colloidal solution of nanostructured silver bisilicate Ag6Si2O7 with particles size of 1-2 nm in deionized water. In vitro studies to evaluate the effect of various ACS concentrations in human tumor cells cultures (breast cancer, colon carcinoma and prostate cancer) were conducted. The highest antitumor activity of ACS was observed in dilutions from 2.7 mg/l to 5.1 mg/l, resulting in the death of tumor cells in all studied cell cultures. In vivo experiments on transplanted Ehrlich carcinoma model in mice consuming 0.75 mg/kg ACS with drinking water revealed significant inhibition of tumor growth since the 14th day of experiment (maximally by 52% on the 28th day, p < 0.05) in comparison with control. Subcutaneous injections of 2.5 mg/kg ACS inhibited Ehrlich's tumor growth on the 7th and 10th days of the experiment (p < 0.05) as compared to control.

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Silver Nanoparticles and Their Antibacterial Applications

International Journal of Molecular Sciences ◽

10.3390/ijms22137202 ◽

2021 ◽

Vol 22 (13) ◽

pp. 7202

Author(s):

Tamara Bruna ◽

Francisca Maldonado-Bravo ◽

Paul Jara ◽

Nelson Caro

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Agents ◽

Multidrug Resistant ◽

Secondary Effects ◽

Cytotoxic Effects ◽

Factors Affecting ◽

Gram Positive Bacteria ◽

Resistant Strains

Silver nanoparticles (AgNPs) have been imposed as an excellent antimicrobial agent being able to combat bacteria in vitro and in vivo causing infections. The antibacterial capacity of AgNPs covers Gram-negative and Gram-positive bacteria, including multidrug resistant strains. AgNPs exhibit multiple and simultaneous mechanisms of action and in combination with antibacterial agents as organic compounds or antibiotics it has shown synergistic effect against pathogens bacteria such as Escherichia coli and Staphylococcus aureus. The characteristics of silver nanoparticles make them suitable for their application in medical and healthcare products where they may treat infections or prevent them efficiently. With the urgent need for new efficient antibacterial agents, this review aims to establish factors affecting antibacterial and cytotoxic effects of silver nanoparticles, as well as to expose the advantages of using AgNPs as new antibacterial agents in combination with antibiotic, which will reduce the dosage needed and prevent secondary effects associated to both.

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Potential In Vitro Inhibition of Selected Plant Extracts against SARS-CoV-2 Chymotripsin-Like Protease (3CLPro) Activity

Foods ◽

10.3390/foods10071503 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1503

Author(s):

Carla Guijarro-Real ◽

Mariola Plazas ◽

Adrián Rodríguez-Burruezo ◽

Jaime Prohens ◽

Ana Fita

Keyword(s):

Plant Extracts ◽

Curcuma Longa ◽

Hydrolysis Product ◽

Resonance Energy ◽

Significant Inhibition ◽

Main Role ◽

Turmeric Extract ◽

Ic50 Value

Antiviral treatments inhibiting Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication may represent a strategy complementary to vaccination to fight the ongoing Coronavirus disease 19 (COVID-19) pandemic. Molecules or extracts inhibiting the SARS-CoV-2 chymotripsin-like protease (3CLPro) could contribute to reducing or suppressing SARS-CoV-2 replication. Using a targeted approach, we identified 17 plant products that are included in current and traditional cuisines as promising inhibitors of SARS-CoV-2 3CLPro activity. Methanolic extracts were evaluated in vitro for inhibition of SARS-CoV-2 3CLPro activity using a quenched fluorescence resonance energy transfer (FRET) assay. Extracts from turmeric (Curcuma longa) rhizomes, mustard (Brassica nigra) seeds, and wall rocket (Diplotaxis erucoides subsp. erucoides) at 500 µg mL−1 displayed significant inhibition of the 3CLPro activity, resulting in residual protease activities of 0.0%, 9.4%, and 14.9%, respectively. Using different extract concentrations, an IC50 value of 15.74 µg mL−1 was calculated for turmeric extract. Commercial curcumin inhibited the 3CLPro activity, but did not fully account for the inhibitory effect of turmeric rhizomes extracts, suggesting that other components of the turmeric extract must also play a main role in inhibiting the 3CLPro activity. Sinigrin, a major glucosinolate present in mustard seeds and wall rocket, did not have relevant 3CLPro inhibitory activity; however, its hydrolysis product allyl isothiocyanate had an IC50 value of 41.43 µg mL−1. The current study identifies plant extracts and molecules that can be of interest in the search for treatments against COVID-19, acting as a basis for future chemical, in vivo, and clinical trials.

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High expression of PSMC2 promotes gallbladder cancer through regulation of GNG4 and predicts poor prognosis

Oncogenesis ◽

10.1038/s41389-021-00330-1 ◽

2021 ◽

Vol 10 (5) ◽

Author(s):

Dawei Zhu ◽

Xing Gu ◽

Zhengyu Lin ◽

Dandan Yu ◽

Jing Wang

Keyword(s):

Gallbladder Cancer ◽

Malignant Tumor ◽

Xenograft Model ◽

Tumor Grade ◽

Significant Inhibition ◽

Mechanistic Study ◽

Downstream Target ◽

Advanced Tumor

AbstractGallbladder cancer (GBC) is a common malignant tumor of the biliary tract, which accounts for 80–95% of biliary tumors worldwide, and is the leading cause of biliary malignant tumor-related death. This study identified PSMC2 as a potential regulator in the development of GBC. We showed that PSMC2 expression in GBC tissues is significantly higher than that in normal tissues, while high PSMC2 expression was correlated with more advanced tumor grade and poorer prognosis. The knockdown of PSMC2 in GBC cells induced significant inhibition of cell proliferation, colony formation and cell motility, while the promotion of cell apoptosis. The construction and observation of the mice xenograft model also confirmed the inhibitory effects of PSMC2 knockdown on GBC development. Moreover, our mechanistic study recognized GNG4 as a potential downstream target of PSMC2, knockdown of which could aggravate the tumor suppression induced by PSMC2 knockdown in vitro and in vivo. In conclusion, for the first time, PSMC2 was revealed as a tumor promotor in the development of GBC, which could regulate cell phenotypes of GBC cells through the interaction with GNG4, and maybe a promising therapeutic target in GBC treatment.

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THU0080 PRECLINICAL CHARACTERIZATION OF TLL018, A NOVEL, HIGHLY POTENT AND SELECTIVE JAK1/TYK2 INHIBITOR FOR TREATING AUTOIMMUNE DISEASES

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2020-eular.1547 ◽

2020 ◽

Vol 79 (Suppl 1) ◽

pp. 252.1-252

Author(s):

X. Liu ◽

F. Tan ◽

C. Liang

Keyword(s):

Bone Resorption ◽

Autoimmune Diseases ◽

Whole Blood ◽

Significant Inhibition ◽

Clinical Development ◽

Therapeutic Window ◽

Collagen Induced Arthritis

Background:Janus kinases (JAKs) are important regulators of intracellular responses triggered by many key proinflammatory cytokines and are clinically validated therapeutic targets for treating various autoimmune diseases. However, current approved JAK inhibitors failed to achieve maximal clinical benefit in part due to their unfavorable selectivity for individual JAKs such as JAK2 and/or JAK3, leading to dose-limiting toxicities or severe toxicities (e.g., thrombosis, anemia, immune suppression). Selective inhibition of JAK1 and/or TYK2 may minimize or avoid some of the toxicities and potentially offer a better therapeutic window for treating autoimmune diseases. No highly selective JAK1/TYK2 inhibitor has been reported to date.Objectives:Discovery of a highly selective JAK1/TYK2 inhibitor that maximally avoids JAK2 and JAK3 inhibition. We described preclinical characterization of a novel, highly potent and selective JAK1/TYK2 inhibitor TLL018 and its potential utility in treating autoimmune diseases such as rheumatoid arthritis (RA).Methods:Using predicting SAR, TLL018 was designed to achieve exquisite selectivity for both JAK1 and TYK2 while sparing JAK2, JAK3 and other human kinases. Its enzyme and cell activities, kinase selectivity, andin vivoefficacy were assessed in a battery of relevant enzyme, cell and whole blood assays, andin vivoarthritis animal models. Additional preclinical DMPK and toxicology studies were conducted to support its clinical development.Results:TLL018 is a highly potent and selective, orally bioavailable JAK1/TYK2 inhibitor against JAK1 (IC50= 4 nM) and TYK2 (IC50= 5 nM) as measured inin vitrokinase assays with ATP concentrations at individual Km. Its potency against JAK2 or JAK3 is greater than 1 µM. Profiling against a panel of over 350 human kinase showed that TLL018 is exclusively selective for JAK1 and TYK2, with ≥ 90-fold selectivity against all other kinases tested. TLL018 exhibited potent cellular activity for JAK1-mediated IL-6 signaling (IC50= 0.6 µM) with greater than 100-fold selectivity against JAK2-mediated cytokine (e.g., TPO) signaling in human whole blood-based assays.Oral administration of TLL018 demonstrated dose-dependent efficacy in commonly studied rat adjuvant-induced arthritis (rAIA) model and mouse collagen-induced arthritis (mCIA) model. Significant inhibition of inflammation, bone resorption, splenomegaly and body weight change was observed in adjuvant-induced disease in rats. In addition, significant inhibition of inflammation, cartilage destruction, bone resorption and histological signs was demonstrated in collagen-induced arthritis in mice. Noticeably, TLL018 exhibited significant anti-inflammation activity at doses that only blocked JAK1 and TYK2 and exerted little inhibition of JAK2 and JAK3.In support of clinical development of TLL018, preclinical ADME and PK studies and IND-enabling toxicology and safety pharmacology studies were completed, confirming that TLL018 possesses excellent ADME and PK properties, and exhibits a clean on-target safety profile.Conclusion:TLL018 is a highly potent and selective JAK1/TYK2 inhibitor that demonstrated excellent efficacy and tolerability in relevant mouse and rat arthritis models. The collective data of its preclinical pharmacology, PK and toxicology showed a favorable pharmaceutical profile, further supporting its development for treating autoimmune diseases including RA. Clinical evaluation of TLL018 is ongoing.Disclosure of Interests:Xiangdong Liu Shareholder of: I own shares of TLL Pharmaceutical LLC, Employee of: I am employed by TLL Pharmaceutical LLC, Fenlai Tan Shareholder of: I own shares of TLL Pharmaceutical LLC, Employee of: I am employed by TLL Pharmaceutical LLC, Chris Liang Shareholder of: I own shares of TLL Pharmaceutical LLC, Employee of: I am employed by TLL Pharmaceutical LLC

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Antimalarial Effect of the Total Glycosides of the Medicinal Plant, Ranunculus japonicus

Pathogens ◽

10.3390/pathogens10050532 ◽

2021 ◽

Vol 10 (5) ◽

pp. 532

Author(s):

Hae-Soo Yun ◽

Sylvatrie-Danne Dinzouna-Boutamba ◽

Sanghyun Lee ◽

Zin Moon ◽

Dongmi Kwak ◽

...

Keyword(s):

Chinese Medicine ◽

Traditional Chinese Medicine ◽

Plasmodium Berghei ◽

Antimalarial Activity ◽

Hematological Parameters ◽

Significant Inhibition ◽

Ic50 Values ◽

The Republic

In traditional Chinese medicine, Ranunculus japonicus has been used to treat various diseases, including malaria, and the young stem of R. japonicus is consumed as a food in the Republic of Korea. However, experimental evidence of the antimalarial effect of R. japonicus has not been evaluated. Therefore, the antimalarial activity of the extract of the young stem of R. japonicus was evaluated in vitro using both chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strains; in vivo activity was evaluated in Plasmodium berghei-infected mice via oral administration followed by a four-day suppressive test focused on biochemical and hematological parameters. Exposure to extracts of R. japonicus resulted in significant inhibition of both chloroquine-sensitive (3D7) and resistant (Dd2) strains of P. falciparum, with IC50 values of 6.29 ± 2.78 and 5.36 ± 4.93 μg/mL, respectively. Administration of R. japonicus also resulted in potent antimalarial activity against P. berghei in infected mice with no associated toxicity; treatment also resulted in improved hepatic, renal, and hematologic parameters. These results demonstrate the antimalarial effects of R. japonicus both in vitro and in vivo with no apparent toxicity.

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The Antitumor Activity of Sodium Selenite Alone and in Combination with Gemcitabine in Pancreatic Cancer: An In Vitro and In Vivo Study

Cancers ◽

10.3390/cancers13133169 ◽

2021 ◽

Vol 13 (13) ◽

pp. 3169

Author(s):

Kevin Doello ◽

Cristina Mesas ◽

Francisco Quiñonero ◽

Gloria Perazzoli ◽

Laura Cabeza ◽

...

Keyword(s):

Pancreatic Cancer ◽

Sodium Selenite ◽

Molecular Mechanisms ◽

Combined Therapy ◽

Significant Inhibition ◽

In Vivo Studies ◽

C57bl Mice ◽

Migration Capacity

Sodium selenite acts by depleting enzymes that protect against cellular oxidative stress. To determine its effect alone or in combination with gemcitabine (GMZ) in pancreatic cancer, we used PANC-1 and Pan02 cell lines and C57BL mice bearing a Pan02-generated tumor. Our results demonstrated a significant inhibition of pancreatic cancer cell viability with the use of sodium selenite alone and a synergistic effect when associated with GMZ. The molecular mechanisms of the antitumor effect of sodium selenite alone involved apoptosis-inducing factor (AIF) and the expression of phospho-p38 in the combined therapy. In addition, sodium selenite alone and in association with GMZ significantly decreased the migration capacity and colony-forming ability, reduced tumor activity in multicellular tumor spheroids (MTS) and decreased sphere formation of cancer stem cells. In vivo studies demonstrated that combined therapy not only inhibited tumor growth (65%) compared to the untreated group but also relative to sodium selenite or GMZ used as monotherapy (up to 40%), increasing mice survival. These results were supported by the analysis of C57BL/6 albino mice bearing a Pan02-generated tumor, using the IVIS system. In conclusion, our results showed that sodium selenite is a potential agent for the improvement in the treatment of pancreatic cancer and should be considered for future human clinical trials.

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