scholarly journals Antitrypanosomal Activity of a New Triazine Derivative, SIPI 1029, In Vitro and in Model Infections

1998 ◽  
Vol 42 (10) ◽  
pp. 2718-2721 ◽  
Author(s):  
Cyrus J. Bacchi ◽  
Marcus Vargas ◽  
Donna Rattendi ◽  
Burt Goldberg ◽  
Weicheng Zhou
Keyword(s):  
Trypanosoma Brucei ◽  
Model Systems ◽  
In Vivo Model ◽  
Trypanosoma Brucei Rhodesiense ◽  
Diminazene Aceturate ◽  
African Trypanosomes ◽  
Cure Rates ◽  
Laboratory Models

ABSTRACT A recently developed diaminotriazine derivative [O,O′-bis(1,2-dihydro-2,2-tetramethylene-4,6-diamino-S-triazin-1-yl)-1,6-hexanediol dihydrochloride; T-46; SIPI 1029] was examined for activity against African trypanosomes in in vitro and in vivo model systems. In vitro, SIPI 1029 was 50% inhibitory for growth of bloodstream trypomastigotes of four strains of Trypanosoma brucei brucei and Trypanosoma brucei rhodesiense at 0.15 to 2.15 nM (50% inhibitory concentrations). In in vivo mouse laboratory models of T. b. rhodesiense clinical isolate infections, SIPI 1029 was curative for 12 of 13 isolates at ≤10 mg/kg of body weight/day for 3 days. In eight infections, a single dose was ≥60% curative, and in six of these, a dose of ≤5 mg/kg was sufficient for ≥60% cure rates. A number of these isolates were resistant to the standard trypanocide melarsoprol (Arsobal) and/or the diamidines diminazene aceturate (Berenil) and pentamidine. SIPI 1029 was also curative in combination withdl-α-difluoromethylornithine (Ornidyl) in a T. b. brucei central nervous system model infection. Some evidence of toxicity was found in dosage regimens of 10 mg/kg/day for 2 or 3 days in which deaths were observed in 6 of 65 animals given this dosage regimen. The activity of SIPI 1029 in this study indicates that this class of compounds (diaminotriazines) should be explored as leads for new human and veterinary trypanocides.

In Vitro and In Vivo Model Systems for the Study of Allergic and Inflammatory Disorders in Man

CHEST Journal ◽  
1985 ◽  
Vol 87 (5) ◽  
pp. 162S-164S ◽  
Author(s):  
Stephen P. Peters ◽  
Robert M. Naclerio ◽  
Alkis Togias ◽  
Robert P. Schleimer ◽  
Donald W. MacGlashan ◽  
...  
Keyword(s):  
Model Systems ◽  
In Vivo Model ◽  
Inflammatory Disorders

scholarly journals Diet, Obesity, and Cancer Progression: Are Adipocytes the Link?

2013 ◽  
Vol 6 ◽  
pp. LPI.S10871 ◽  
Author(s):  
Paul Toren ◽  
Benjamin C. Mora ◽  
Vasundara Venkateswaran
Keyword(s):  
Tumor Microenvironment ◽  
Cancer Progression ◽  
Tumor Biology ◽  
Model Systems ◽  
In Vivo Model ◽  
Diet Induced Obesity ◽  
Breast And Prostate Cancer ◽  
Obesity And Cancer

Obesity has been linked to more aggressive characteristics of several cancers, including breast and prostate cancer. Adipose tissue appears to contribute to paracrine interactions in the tumor microenvironment. In particular, cancer-associated adipocytes interact reciprocally with cancer cells and influence cancer progression. Adipokines secreted from adipocytes likely form a key component of the paracrine signaling in the tumor microenvironment. In vitro coculture models allow for the assessment of specific adipokines in this interaction. Furthermore, micronutrients and macronutrients present in the diet may alter the secretion of adipokines from adipocytes. The effect of dietary fat and specific fatty acids on cancer progression in several in vivo model systems and cancer types is reviewed. The more common approaches of caloric restriction or diet-induced obesity in animal models establish that such dietary changes modulate tumor biology. This review seeks to explore available evidence regarding how diet may modulate tumor characteristics through changes in the role of adipocytes in the tumor microenvironment.

scholarly journals In vivo efficacies of 5'-methylthioadenosine analogs as trypanocides.

1997 ◽  
Vol 41 (10) ◽  
pp. 2108-2112 ◽  
Author(s):  
C J Bacchi ◽  
K Sanabria ◽  
A J Spiess ◽  
M Vargas ◽  
C J Marasco ◽  
...  
Keyword(s):  
Trypanosoma Brucei ◽  
East African ◽  
Trypanosoma Brucei Rhodesiense ◽  
Polyamine Biosynthesis ◽  
Substrate Analogs ◽  
Osmotic Pumps ◽  
Derivatives Of ◽  
Ribose Moiety

5'-Deoxy-5'-(methylthio)adenosine (MTA), a key by-product of polyamine biosynthesis, is cleaved by MTA phosphorylase and is salvaged as adenine and, through conversion of the ribose moiety, methionine. An analog of MTA, 5'-deoxy-5'-(hydroxyethylthio)adenosine (HETA), is a substrate for trypanosome MTA phosphorylase and is active in vitro and in vivo against Trypanosoma brucei brucei, an agent of bovine trypanosomiasis. In this study, HETA and three O-acylated HETA derivatives were examined for their activities against model infections of T. b. brucei and Trypanosoma brucei rhodesiense, the agent of East African sleeping sickness. HETA was curative (>60%) for infections caused by 5 of 11 clinical isolates of T. b. rhodesiense when it was given to mice at 200 mg/kg of body weight for 7 days as a continuous infusion in osmotic pumps. HETA at 150 to 200 mg/kg also extended the life spans of the mice infected with four additional isolates two- to fivefold. Di- and tri-O-acetylated derivatives of HETA also proved curative for the infections, while a tri-O-propionyl derivative, although also curative, was not as effective. This study indicates that substrate analogs of MTA should be given important consideration for development as novel chemotherapies against African trypanosomiasis.

scholarly journals Unbiased in vivo preclinical evaluation of anticancer drugs identifies effective therapy for the treatment of pancreatic adenocarcinoma

2020 ◽  
Vol 117 (48) ◽  
pp. 30670-30678
Author(s):  
Olivera Grbovic-Huezo ◽  
Kenneth L. Pitter ◽  
Nicolas Lecomte ◽  
Joseph Saglimbeni ◽  
Gokce Askan ◽  
...  
Keyword(s):  
Large Scale ◽  
Single Agent ◽  
Model Systems ◽  
Ductal Adenocarcinoma ◽  
In Vivo Model ◽  
Cancer Therapies ◽  
Hsp90 Inhibition ◽  
Dismal Prognosis

Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed at an advanced stage, which limits surgical options and portends a dismal prognosis. Current oncologic PDAC therapies confer marginal benefit and, thus, a significant unmet clinical need exists for new therapeutic strategies. To identify effective PDAC therapies, we leveraged a syngeneic orthotopic PDAC transplant mouse model to perform a large-scale, in vivo screen of 16 single-agent and 41 two-drug targeted therapy combinations in mice. Among 57 drug conditions screened, combined inhibition of heat shock protein (Hsp)-90 and MEK was found to produce robust suppression of tumor growth, leading to an 80% increase in the survival of PDAC-bearing mice with no significant toxicity. Mechanistically, we observed that single-agent MEK inhibition led to compensatory activation of resistance pathways, including components of the PI3K/AKT/mTOR signaling axis, which was overcome with the addition of HSP90 inhibition. The combination of HSP90(i) + MEK(i) was also active in vitro in established human PDAC cell lines and in vivo in patient-derived organoid PDAC transplant models. These findings encourage the clinical development of HSP90(i) + MEK(i) combination therapy and highlight the power of clinically relevant in vivo model systems for identifying cancer therapies.

scholarly journals ENHANCED FLUORESCENCE IMAGING WITH DMSO-MEDIATED OPTICAL CLEARING

2010 ◽  
Vol 03 (03) ◽  
pp. 153-158 ◽  
Author(s):  
SANJEEV KARMA ◽  
JAMES HOMAN ◽  
CHARLES STOIANOVICI ◽  
BERNARD CHOI
Keyword(s):  
Fluorescence Emission ◽  
Model Systems ◽  
In Vivo Studies ◽  
In Vivo Model ◽  
Fluorescence Signal ◽  
Optical Clearing ◽  
Treated Site

Recent studies have demonstrated that topical application of glycerol on intact skin does not affect its optical scattering properties. Investigators from our research group recently revisited the use of dimethyl sulfoxide (DMSO) as an agent with optical clearing potential. We address the use of optical clearing to enhance quantitation of subsurface fluorescence emission. We employed both in vitro and in vivo model systems to study the effect of topical DMSO application on fluorescence emission. Our in vitro experiments performed on a tissue-simulating phantom suggest that DMSO-mediated optical clearing enables enhanced characterization of subsurface fluorophores. With topical DMSO application, a marked increase in fluorescence emission was observed. After 30 min, the fluorescence signal at the DMSO-treated site was 9× greater than the contralateral saline-treated site. This ratio increased to 13× at 105 min after agent application. In summary, DMSO is an effective optical clearing agent for improved fluorescence emission quantitation and warrants further study in preclinical in vivo studies. Based on outcomes from previous clinical studies on the toxicity profile of DMSO, we postulate that clinical application of DMSO as an optical clearing agent, can be performed safely, although further study is warranted.

scholarly journals De novo disease-associated mutations in KIF1A dominant negatively inhibit axonal transport of synaptic vesicle precursors

2021 ◽  
Author(s):  
Yuzu Anazawa ◽  
Tomoki Kita ◽  
Kumiko Hayashi ◽  
Shinsuke Niwa
Keyword(s):  
Synaptic Vesicle ◽  
Axonal Transport ◽  
De Novo ◽  
Molecular Motor ◽  
Model Systems ◽  
In Vitro Assays ◽  
In Vivo Model ◽  
Wild Type

KIF1A is a kinesin superfamily molecular motor that transports synaptic vesicle precursors in axons. Mutations in Kif1a lead to a group of neuronal diseases called KIF1A-associated neuronal disorder (KAND). KIF1A forms a homodimer and KAND mutations are mostly de novo and autosomal dominant; however, it is not known whether the function of wild-type KIF1A is inhibited by disease-associated KIF1A. No reliable in vivo model systems to analyze the molecular and cellular biology of KAND have been developed; therefore, here, we established Caenorhabditis elegans models for KAND using CRISPR/cas9 technology and analyzed defects in axonal transport. In the C. elegans models, heterozygotes and homozygotes exhibited reduced axonal transport phenotypes. In addition, we developed in vitro assays to analyze the motility of single heterodimers composed of wild-type KIF1A and disease-associated KIF1A. Disease-associated KIF1A significantly inhibited the motility of wild-type KIF1A when heterodimers were formed. These data indicate the molecular mechanism underlying the dominant nature of de novo KAND mutations.

scholarly journals Differential virulence of Trypanosoma brucei rhodesiense isolates does not influence the outcome of treatment with anti-trypanosomal drugs in the mouse model

2020 ◽  
Author(s):  
Kariuki Ndung’u ◽  
Grace Adira Murilla ◽  
John Kibuthu Thuita ◽  
Geoffrey Njuguna Ngae ◽  
Joanna Eseri Auma ◽  
...  
Keyword(s):  
Trypanosoma Brucei ◽  
Post Infection ◽  
Drug Resistant ◽  
Weight Changes ◽  
Trypanosoma Brucei Rhodesiense ◽  
Diminazene Aceturate ◽  
Reference Drug ◽  
Western Kenya ◽  
Biotechnology Research ◽  
Cure Rates

AbstractWe assessed the virulence and anti-trypanosomal drug sensitivity patterns of Trypanosoma brucei rhodesiense (Tbr) isolates in the Kenya Agricultural and Livestock Research Organization-Biotechnology Research Institute (KALRO-BioRI) cryobank. Specifically, the study focused on Tbr clones originally isolated from the western Kenya/eastern Uganda focus of human African Trypanosomiasis (HAT). Twelve (12) Tbr clones were assessed for virulence using groups(n=10) of Swiss White Mice monitored for 60 days post infection (dpi). Based on survival time, four classes of virulence were identified: (a) very-acute: 0-15, (b) acute: 16-30, (c) sub-acute: 31-45 and (d) chronic: 46-60 dpi. Other virulence biomarkers identified included: prepatent period (pp), parasitaemia progression, packed cell volume (PCV) and body weight changes. The test Tbr clones together with KALRO-BioRi reference drug-resistant and drug sensitive isolates were then tested for sensitivity to melarsoprol (mel B) pentamidine, diminazene aceturate and suramin, using mice groups (n= 5) treated with single doses of each drug at 24 hours post infection. Our results showed that the clones were distributed among four classes of virulence as follows: 3/12 (very-acute), 3/12 (acute), 2/12 (sub-acute) and 4/12 (chronic) isolates. Differences in survivorship, parasitaemia progression and PCV were significant (P<0.001) and correlated. The isolate considered to be drug resistant at KALRO-BioRI, KETRI 2538, was confirmed to be resistant to melarsoprol, pentamidine and diminazene aceturate but it was not resistant to suramin. At least 80% cure rates of all the test isolates was achieved with melarsoprol (1mg/Kg and 20 mg/kg), pentamidine (5 and 20 mg/kg), diminazene aceturate (5 mg/kg) and suramin (5 mg/kg) indicating that the isolates were not resistant to any of the drugs despite the differences in virulence. This study provides evidence of variations in virulence of Tbr isolates from a single HAT focus and confirms that these variations are not a significant determinant of isolate sensitivity to anti-trypanosomal drugs.

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