Evaluation of in vitro treatments against the causative agent of Diadema antillarum scuticociliatosis (DaSc).

In the 1980s, a mass die-off of the long-spined sea urchin Diadema antillarum occurred on Florida and Caribbean coral reefs. D. antillarum populations largely did not recover, and in 2022, remaining populations experienced another mass mortality event. A ciliate most similar to Philaster apodigitiformis was identified as the causative agent of the 2022 event, which was named D. antillarum scuticociliatosis (DaSc). Here, we investigated possible treatments for this pathogen. We tested the efficacy of 10 compounds at final concentrations of 100, 50, 25, 12.5, 6.25, and 3.13 µM, or a 10-fold serial dilution series, against ciliates cultured from an infected D. antillarum specimen. Of the tested compounds, 8 induced 100% ciliate mortality at some dose after 24 h. The most effective (defined as those requiring the lowest dose to induce 100% ciliate mortality) were quinacrine and tomatine (both effective at 12.5 µM), followed by furaltadone and plumbagin (25 µM), bithionol sulfoxide and 2'4' dihydroxychalcone (50 µM), and oxyclozanide and carnidazole (100 µM). Toltrazuril and a commercially available anticiliate product containing naphthoquinones were not effective at any dose tested. Shortened (15 min) time trials were performed using ciliate cultures reared in natural seawater to better reflect natural environmental conditions, and revealed that 2 of the compounds (quinacrine and tomatine) induced 100% ciliate mortality at 100 µM, with tomatine also effective at 50 µM. This study identified several treatments effective against the causative agent of DaSc in vitro, but their toxicity and utility in vivo remain unknown.

Cardio- and Vasoprotective Effects of Quinacrine in an In Vivo Rat Model of Myocardial Ischemia/Reperfusion Injury.

This study aimed to investigate the cardioprotective effect of quinacrine in an in vivo model of myocardial ischemia/reperfusion injury. A 30-min regional myocardial ischemia followed by a 2-h reperfusion was modeled in anesthetized Wistar rats. Starting at the last minute of ischemia and during the first 9 min of reperfusion the rats in the control (n=8) and experimental (n=9) groups were injected with 0.9% NaCl and quinacrine solution (5 mg/kg), respectively. The area at risk and infarct size were evaluated by "double staining" with Evans blue and triphenyltetrazolium chloride. To assess vascular permeability in the area at risk zone, indocyanine green (ICG) and thioflavin S (ThS) were injected intravenously at the 90th and 120th minutes of reperfusion, respectively, to assess the no-reflow zone. The images of ICG and ThS fluorescence in transverse sections of rat hearts were obtained using a FLUM multispectral fluorescence organoscope. HR tended to decrease by 13% after intravenous administration of quinacrine and then recovered within 50 min. Quinacrine reduced the size of the necrotic zone (p=0.01), vascular permeability in the necrosis region, and the no-reflow area (p=0.027); at the same time, the area at risk did not significantly differ between the groups. Intravenous administration of quinacrine at the beginning of reperfusion of the rat myocardium reduces no-reflow phenomenon and infarct size.

Quinacrine - The Winding Road from the Most Important Antimalarial of Its Time to an Indispensable Antiparasitic (Orphan) Drug of our Days.

Quinacrine, the main antimalarial drug during World War II, has had a chequered history that included the successful repurposing as an intrapleural sclerosant for the treatment of malignant pleural effusions, a non-surgical method of female sterilisation, and the use as an immunomodulatory drug in lupus erythematosus. While no longer used for these former indications, quinacrine (re)emerged as an indispensable second-line drug for the treatment of nitroimidazole-refractory Giardia duodenalis infections, and thus depicts an indispensable "orphan drug".

Quinacrine Treatment of Nitroimidazole-Refractory Giardiasis.

BACKGROUND: Limited evidence exists on efficacy and tolerability of quinacrine for nitroimidazole-refractory giardiasis. METHODS: Nitroimidazole-refractory giardiasis cases, defined as microbiologically (microscopy and/or PCR) confirmed treatment failure after 2 courses, during 2008-2020, were retrospectively identified. RESULTS: Of 87 patients, 54 (62%) had visited India. Quinacrine was used in 54 (62%); 51 received monotherapy and 3 combined with metronidazole. Only 3 had positive stool samples with persisting symptoms after quinacrine treatment (94% parasitological efficacy) and all were cured after a second treatment. One (1.9%) had mild adverse effects recorded. CONCLUSIONS: Quinacrine is an effective treatment for nitroimidazole-refractory giardiasis with good tolerability.

Repurposing quinacrine for treatment-refractory cancer.

Quinacrine, also known as mepacrine, has originally been used as an antimalarial drug for close to a century, but was recently rediscovered as an anticancer agent. The mechanisms of anticancer effects of quinacrine are not well understood. The anticancer potential of quinacrine was discovered in a screen for small molecule activators of p53, and was specifically shown to inhibit NFκB suppression of p53. However, quinacrine can cause cell death in cells that lack p53 or have p53 mutations, which is a common occurrence in many malignant tumors including high grade serous ovarian cancer. Recent reports suggest quinacrine may inhibit cancer cell growth through multiple mechanisms including regulating autophagy, FACT (facilitates chromatin transcription) chromatin trapping, and the DNA repair process. Additional reports also suggest quinacrine is effective against chemoresistant gynecologic cancer. In this review, we discuss anticancer effects of quinacrine and potential mechanisms of action with a specific focus on gynecologic and breast cancer where treatment-refractory tumors are associated with increased mortality rates. Repurposing quinacrine as an anticancer agent appears to be a promising strategy based on its ability to target multiple pathways, its selectivity against cancer cells, and the synergistic cytotoxicity when combined with other anticancer agents with limited side effects and good tolerability profile.

PARP inhibitor BMN-673 induced apoptosis by trapping PARP-1 and inhibiting base excision repair via modulation of pol-ß in chromatin of breast cancer cells.

PARP inhibitors emerged as clinically effective anti-tumor agents in combination with DNA damaging agents but the toxicity of DNA damaging agents and their off-target effects caused serious problems in cancer therapy. They confer cytotoxicity in cancer cells both by catalytic inhibition and trapping of PARP-1 at the DNA damage site. There is a lack of direct evidence to quantitatively determine the trapped PARP-1 in cellular DNA. Here, we have precisely evaluated the mechanism of PARP trapping mediated anti-cancer action of Quinacrine (QC), BMN-673, and their combination (QC + BMN-673) in breast cancer cells. We introduced a strategy to measure the cellular PARP trapping potentiality of BMN-673 in QC pretreated cells using a fluorescence-based assay system. It was found that QC+ BMN-673 induced apoptosis by triggering DNA damage in breast cancer cells. Treatment with QC + BMN-673 stimulated the expression of PARP-1 in the chromatin compared to that of PARP-2 and PARP-3. QC + BMN-673 treatment also caused a dose-dependent and time-dependent accumulation of PARP-1 and inhibition of PARylation in the chromatin. Upregulation of BER components (pol-ß and FEN-1), an unchanged HR and NHEJ pathway proteins, and reduction of luciferase activity of the cells transfected with R-p21-P (LP-BER) were noted in combined drug-treated cells. Interestingly, silencing of pol-ß resulted in unchanged PARP-1 trapping and PAR activity in the chromatin with increasing time after QC + BMN-673 treatment without altering APC and FEN-1 expression. Thus, our data suggested that the QC + BMN-673 augmented breast cancer cell death by pol-ß mediated repair inhibition primarily through trapping of PARP-1 besides PARP-1 catalytic inhibition.

Multimodal Investigation into the Interaction of Quinacrine with Microcavity-Supported Lipid Bilayers.

Quinacrine is a versatile drug that is widely recognized for its antimalarial action through its inhibition of the phospholipase enzyme. It also has antianthelmintic and antiprotozoan activities and is a strong DNA binder that may be used to combat multidrug resistance in cancer. Despite extensive cell-based studies, a detailed understanding of quinacrine's influence on the cell membrane, including permeability, binding, and rearrangement at the molecular level, is lacking. Herein, we apply microcavity-suspended lipid bilayers (MSLBs) as in vitro models of the cell membrane comprising DOPC, DOPC:Chol(3:1), and DOPC:SM:Chol(2:2:1) to investigate the influence of cholesterol and intrinsic phase heterogeneity induced by mixed-lipid composition on the membrane interactions of quinacrine. Using electrochemical impedance spectroscopy (EIS) and surface-enhanced Raman spectroscopy (SERS) as label-free surface-sensitive techniques, we have studied quinacrine interaction and permeability across the different MSLBs. Our EIS data reveal that the drug is permeable through ternary DOPC:SM:Chol and DOPC-only bilayer compositions. In contrast, the binary cholesterol/DOPC membrane arrested permeation, yet the drug binds or intercalates at this membrane as reflected by an increase in membrane impedance. SERS supported the EIS data, which was utilized to gain structural insights into the drug-membrane interaction. Our SERS data also provides a simple but powerful label-free assessment of drug permeation because a significant SERS enhancement of the drug's Raman signature was observed only if the drug accessed the plasmonic interior of the pore cavity passing through the membrane. Fluorescent lifetime correlation spectroscopy (FLCS) provides further biophysical insight, revealing that quinacrine binding increases the lipid diffusivity of DOPC and the ternary membrane while remarkably decreasing the lipid diffusivity of the DOPC:Chol membrane. Overall, because of its adaptability to multimodal approaches, the MSLB platform provides rich and detailed insights into drug-membrane interactions, making it a powerful tool for in vitro drug screening.

Increased CD69+CCR7+ circulating activated T cells and STAT3 expression in cutaneous lupus erythematosus patients recalcitrant to antimalarials.

BACKGROUND: Antimalarials are first-line systemic therapy for cutaneous lupus erythematosus (CLE). While some patients unresponsive to hydroxychloroquine (HCQ) alone benefit from the addition of quinacrine (QC), a subset of patients is refractory to both antimalarials. METHODS: We classified CLE patients as HCQ-responders, HCQ+QC-responders, or HCQ+QC-nonresponders to compare immune profiles. Immunohistochemistry, immunofluorescence, and qRT-PCR were used to characterize inflammatory cells and cytokines in lesional skin. RESULTS: Immunohistochemistry showed that CD69+ T cells were higher in HCQ+QC-nonresponders compared to HCQ- and HCQ+QC-responders (p < 0.05). Immunofluorescence further identified these cells as CD69+CCR7+ circulating activated T cells. Myeloid dendritic cells were significantly higher in HCQ+QC-responders compared to both HCQ-responders and HCQ+QC-nonresponders. Plasmacytoid dendritic cells were significantly increased in HCQ-responders compared to HCQ- and HCQ+QC-nonresponders. No differences were found in the number of autoreactive T cells, MAC387+ cells, and neutrophils among the groups. CLASI scores of the HCQ+QC-nonresponder group positively correlated with CD69+CCR7+ circulating activated T cells (r = 0.6335, p < 0.05) and MAC387+ cells (r = 0.5726, p < 0.05). IL-17 protein expression was higher in HCQ+QC-responders compared to HCQ-responders or HCQ+QC-nonresponders, while IL-22 protein expression did not differ. mRNA expression demonstrated increased STAT3 expression in a subset of HCQ+QC-nonresponders. CONCLUSION: An increased number of CD69+CCR7+ circulating activated T cells and a strong correlation with CLASI scores in the HCQ+QC-nonresponders suggest these cells are involved in antimalarial-refractory skin disease. STAT3 is also increased in HCQ+QC-nonresponders and may also be a potential target for antimalarial-refractory skin disease.

NIR irradiation enhances the apoptotic potentiality of quinacrine-gold hybrid nanoparticles by modulation of HSP-70 in oral cancer stem cells.

Cancer stem cells (CSCs) are the tumor cell subpopulations that can self-renew, differentiate, initiate and maintain tumor growth. CSCs are frequently drug-resistant, resulting in tumor recurrence, metastasis, and angiogenesis. Herein, using in vitro oral squamous cell carcinoma (OSCC) CSCs and in vivo xenograft mice model, we have systematically studied the apoptotic potentiality of quinacrine-gold hybrid nanoparticle (QAuNP) and its underlying mechanism after NIR irradiation. QAuNP + NIR caused DNA damage and induced apoptosis in SCC-9-CSCs by deregulating mitochondrial membrane potential (ΔΨm) and activation of ROS. Upregulation of CASPASE-3 and DR-5/DR-4 and reduction of heat shock protein (HSP-70) up to 5-fold were also noticed upon the treatment. The increased expression of DR-5 and CASPASE-3 and decreased expression of HSP-70, CD-44 and Ki-67 were also noted in the xenograft mice treated with QAuNP + NIR + TRAIL. Thus, data suggest that the combined treatment enhances apoptosis in OSCC-CSCs by modulating HSP-70 in the DISC.

Theranostic Platforms Based on Silica and Magnetic Nanoparticles Containing Quinacrine, Chitosan, Fluorophores, and Quantum Dots.

In this paper, we describe the synthesis of multilayer nanoparticles as a platform for the diagnosis and treatment of ischemic injuries. The platform is based on magnetite (MNP) and silica (SNP) nanoparticles, while quinacrine is used as an anti-ischemic agent. The synthesis includes the surface modification of nanoparticles with (3-glycidyloxypropyl)trimethoxysilane (GPMS), the immobilization of quinacrine, and the formation of a chitosan coating, which is used to fix the fluorophore indocyanine green (ICG) and colloidal quantum dots AgInS2/ZnS (CQDs), which serve as secondary radiation sources. The potential theranostic platform was studied in laboratory animals.

Discovery of Quinacrine as a Potent Topo II and Hsp90 Dual-Target Inhibitor, Repurposing for Cancer Therapy.

Topo II and Hsp90 are promising targets. In this study, we first verified the structural similarities between Topo IIα ATPase and Hsp90α N-ATPase. Subsequently, 720 compounds from the Food and Drug Administration (FDA) drug library and kinase library were screened using the malachite green phosphate combination with the Topo II-mediated DNA relaxation and MTT assays. Subsequently, the antimalarial drug quinacrine was found to be a potential dual-target inhibitor of Topo II and Hsp90. Mechanistic studies showed that quinacrine could specifically bind to the Topo IIα ATPase domain and inhibit the activity of Topo IIα ATPase without impacting DNA cleavage. Furthermore, our study revealed that quinacrine could bind Hsp90 N-ATPase and inhibit Hsp90 activity. Significantly, quinacrine has broad antiproliferation activity and remains sensitive to the multidrug-resistant cell line MCF-7/ADR and the atypical drug-resistant tumor cell line HL-60/MX2. Our study identified quinacrine as a potential dual-target inhibitor of Topo II and Hsp90, depending on the ATP-binding domain, positioning it as a hit compound for further structural modification.

Safranal Induces Vasorelaxation by Inhibiting Ca2+ Influx and Na+/Ca2+ Exchanger in Isolated Rat Aortic Rings.

Introduction: Safranal, which endows saffron its unique aroma, causes vasodilatation and has a hypotensive effect in animal studies, but the mechanisms of these effects are unknown. In this study, we investigated the mechanisms of safranal vasodilation. Methods: Isolated rat endothelium-intact or -denuded aortic rings were precontracted with phenylephrine and then relaxed with safranal. To further assess the involvement of nitric oxide, prostaglandins, guanylate cyclase, and phospholipase A2 in safranal-induced vasodilation, aortic rings were preincubated with L-NAME, indomethacin, methylene blue, or quinacrine, respectively, then precontracted with phenylephrine, and safranal concentration-response curves were established. To explore the effects of safranal on Ca2+ influx, phenylephrine and CaCl2 concentration-response curves were established in the presence of safranal. Furthermore, the effect of safranal on aortic rings in the presence of ouabain, a Na+-K+ ATPase inhibitor, was studied to explore the contribution of Na+/Ca2+ exchanger to this vasodilation. Results: Safranal caused vasodilation in endothelium-intact and endothelium-denuded aortic rings. The vasodilation was not eliminated by pretreatment with L-NAME, indomethacin, methylene blue, or quinacrine, indicating the lack of a role for NO/cGMP. Safranal significantly inhibited the maximum contractions induced by phenylephrine, or by CaCl2 in Ca2+-free depolarizing buffer. Safranal also relaxed contractions induced by ouabain, but pretreatment with safranal totally abolished the development of ouabain contractions. Discussion/Conclusion: Inhibition of Na+-K+ ATPase by ouabain leads to the accumulation of Na+ intracellularly, forcing the Na+/Ca2+ exchanger to work in reverse mode, thus causing a contraction. Inhibition of the development of this contraction by preincubation with safranal indicates that safranal inhibited the Na+/Ca2+ exchanger. We conclude that safranal vasodilation is mediated by the inhibition of calcium influx from extracellular space through L-type Ca2+ channels and by the inhibition of the Na+/Ca2+ exchanger.

Efficacy and Tolerability of Quinacrine Monotherapy and Albendazole Plus Chloroquine Combination Therapy in Nitroimidazole-Refractory Giardiasis: A TropNet Study.

BACKGROUND: Giardiasis failing nitroimidazole first-line treatment is an emerging problem in returning European travelers. We present data on the efficacy and tolerability of 2 second-line treatment regimens. METHODS: This prospective, open-label, multicenter study assessed the efficacy and tolerability of quinacrine monotherapy (100 mg 3 times per day for 5 days) and albendazole plus chloroquine combination therapy (400 mg twice daily plus 155 mg twice daily for 5 days) in nitroimidazole-refractory giardiasis. The defined end points were the clinical outcome, assessed at week 5 after treatment and the parasitological outcome, assessed using microscopy of 2 stool samples, ≥2 to ≤5 weeks after treatment. RESULTS: A total of 106 patients were included in the study. Quinacrine achieved clinical and parasitological cure in 81% (59/73) and 100% (56/56), respectively. Albendazole plus chloroquine achieved clinical and parasitological cure in 36% (12/33) and 48% (12/25), respectively. All patients (9/9) who clinically and parasitologically failed albendazole plus chloroquine treatment and opted for retreatment with quinacrine achieved clinical cure. Mild to moderate treatment-related adverse events were reported by 45% and 30% of patients treated with quinacrine and albendazole plus chloroquine, respectively. One patient treated with quinacrine developed severe neuropsychiatric side effects. The majority of nitroimidazole-refractory Giardia infections (57%) were acquired in India. CONCLUSIONS: Quinacrine was a highly effective treatment in nitroimidazole-refractory giardiasis, but patients should be cautioned on the low risk of severe neuropsychiatric adverse event. Albendazole plus chloroquine had a low cure rate in nitroimidazole-refractory giardiasis. Nitroimidazole-refractory giardiasis was primarily seen in travelers returning from India.

Comparison of chloroquine-like molecules for lysosomal inhibition and measurement of autophagic flux in the brain.

Measurement of autophagic flux in vivo is critical to understand how autophagy can be used to combat disease. Neurodegenerative diseases have a special relationship with autophagy, which makes measurement of autophagy in the brain a significant research priority. Currently, measurement of autophagic flux is possible through use of transgenic constructs, or application of a lysosomal inhibitor such as chloroquine. Unfortunately, chloroquine is not useful for measuring autophagic flux in the brain and the use of transgenic animals necessitates cross-breeding of transgenic strains and maintenance of lines, which is costly. To find a drug that could block lysosomal function in the brain for the measurement of autophagic flux, we selected compounds from the literature that appeared to have similar properties to chloroquine and tested their ability to inhibit autophagic flux in cell culture and in mice. These chemicals included chloroquine, quinacrine, mefloquine, promazine and trifluoperazine. As expected, chloroquine blocked lysosomal degradation of the autophagic protein LC3B-II in cell culture. Quinacrine also inhibited autophagic flux in cell culture. Other compounds tested were not effective. When injected into mice, chloroquine caused accumulation of LC3B-II in heart tissue, and quinacrine was effective at blocking LC3B-II degradation in male, but not female skeletal muscle. None of the compounds tested were useful for measuring autophagic flux in the brain. During this study we also noted that the vehicle DMSO powerfully up-regulated LC3B-II abundance in tissues. This study shows that chloroquine and quinacrine can both be used to measure autophagic flux in cells, and in some peripheral tissues. However, measurement of flux in the brain using lysosomal inhibitors remains an unresolved research challenge.

Cationic Compounds with SARS-CoV-2 Antiviral Activity and Their Interaction with Organic Cation Transporter/Multidrug and Toxin Extruder Secretory Transporters.

In the wake of the COVID-19 pandemic, drug repurposing has been highlighted for rapid introduction of therapeutics. Proposed drugs with activity against SARS-CoV-2 include compounds with positive charges at physiologic pH, making them potential targets for the organic cation secretory transporters of kidney and liver, i.e., the basolateral organic cation transporters, OCT1 and OCT2; and the apical multidrug and toxin extruders, MATE1 and MATE2-K. We selected several compounds proposed to have in vitro activity against SARS-CoV-2 (chloroquine, hydroxychloroquine, quinacrine, tilorone, pyronaridine, cetylpyridinium, and miramistin) to test their interaction with OCT and MATE transporters. We used Bayesian machine learning models to generate predictions for each molecule with each transporter and also experimentally determined IC50 values for each compound against labeled substrate transport into CHO cells that stably expressed OCT2, MATE1, or MATE2-K using three structurally distinct substrates (atenolol, metformin and 1-methyl-4-phenylpyridinium) to assess the impact of substrate structure on inhibitory efficacy. For the OCTs substrate identity influenced IC50 values, although the effect was larger and more systematic for OCT2. In contrast, inhibition of MATE1-mediated transport was largely insensitive to substrate identity. Unlike MATE1, inhibition of MATE2-K was influenced, albeit modestly, by substrate identity. Maximum unbound plasma concentration/IC50 ratios were used to identify potential clinical DDI recommendations; all the compounds interacted with the OCT/MATE secretory pathway, most with sufficient avidity to represent potential DDI issues for secretion of cationic drugs. This should be considered when proposing cationic agents as repurposed antivirals. SIGNIFICANCE STATEMENT: Drugs proposed as potential COVID-19 therapeutics based on in vitro activity data against SARS-CoV-2 include compounds with positive charges at physiological pH, making them potential interactors with the OCT/MATE renal secretory pathway. We tested seven such molecules as inhibitors of OCT1/2 and MATE1/2-K. All the compounds blocked transport activity regardless of substrate used to monitor activity. Suggesting that plasma concentrations achieved by normal clinical application of the test agents could be expected to influence the pharmacokinetics of selected cationic drugs.

Quinacrine is not a vital fluorescent probe for vesicular ATP storage.

Quinacrine, a fluorescent amphipathic amine, has been used as a vital fluorescent probe to visualize vesicular storage of ATP in the field of purinergic signaling. However, the mechanism(s) by which quinacrine represents vesicular ATP storage remains to be clarified. The present study investigated the validity of the use of quinacrine as a vial fluorescent probe for ATP-storing organelles. Vesicular nucleotide transporter (VNUT), an essential component for vesicular storage and ATP release, is present in very low density lipoprotein (VLDL)-containing secretory vesicles in hepatocytes. VNUT gene knockout (Vnut-/-) or clodronate treatment, a VNUT inhibitor, disappeared vesicular ATP release (Tatsushima et al., Biochim Biophys Acta Molecular Basis of Disease 2021, e166013). Upon incubation of mice's primary hepatocytes, quinacrine accumulates in a granular pattern into the cytoplasm, sensitive to 0.1-µM bafilomycin A1, a vacuolar ATPase (V-ATPase) inhibitor. Neither Vnut-/- nor treatment of clodronate affected quinacrine granular accumulation. In vitro, quinacrine is accumulated into liposomes upon imposing inside acidic transmembranous pH gradient (∆pH) irrespective of the presence or absence of ATP. Neither ATP binding on VNUT nor VNUT-mediated uptake of ATP was affected by quinacrine. Consistently, VNUT-mediated uptake of quinacrine was negligible or under the detection limit. From these results, it is concluded that vesicular quinacrine accumulation is not due to a consequence of its interaction with ATP but due to ∆pH-driven concentration across the membranes as an amphipathic amine. Thus, quinacrine is not a vital fluorescent probe for vesicular ATP storage.

Clinical phenotypes and therapeutic responses in cutaneous-predominant sarcoidosis: 6-year experience in a tertiary referral service.

BACKGROUND: There is a limited evidence base for the treatment of cutaneous sarcoidosis. OBJECTIVE: To describe treatment modalities and responses in patients with predominantly cutaneous sarcoidosis, in addition to clinical characteristics and prevalence of systemic disease. METHODS: Data were prospectively collected over a 6-year period. The Cutaneous Sarcoidosis Activity and Morphology Index was used to assess treatment effectiveness. RESULTS: In total, 47 patients with biopsy-confirmed cutaneous sarcoidosis were identified. Morphologically, the most common lesions were papules (49%) and plaques (42.6%). The most commonly affected sites were the head and neck (79%); 89.4% had systemic as well as cutaneous disease; 77% received systemic corticosteroid therapy, while 87% required further steroid-sparing treatment; 40% achieved clinical remission with hydroxychloroquine (HCQ) and 88% achieved clinical remission with methotrexate (MTX). OR of achieving remission on MTX compared with HCQ was 9.8 (95% CI 2.4-40.4, P = 0.001). MTX was superior to both azathioprine (AZA) (OR = 22; 95% CI 1.7-285.9; P = 0.02) and mycophenolate mofetil (MMF) (OR = 22; 95% CI 1.7-285.9; P = 0.02) in achieving remission. CONCLUSION: HCQ is effective and well-tolerated. MTX was associated with significantly increased probability of achieving clinical remission compared with AZA and MMF.

What happened to quinacrine non-surgical female sterilization?

Quinacrine sterilization (QS) is a nonsurgical female method used by more than 175,000 women in over 50 countries. With FDA approval, QS is expected to be used by hundreds of millions of women. The negative international health consequences of the results of a 2-year rat study in 2010 by Cancel et al. in Regulatory Toxicology and Pharmacology (RTP) (56:156-165) are incalculable. S1C(R2) was ignored in this study, including the fundamental concept of maximum tolerated dose (MTD), which resulted in the use of massive doses (up to 35 times the MTD) which killed many of the rats and destroyed the uterus of survivors. The design of this rat study was built on the false assertion that this study mimics what happens in women. Cancel et al. (2010), concludes it "seems most likely" that genotoxicity was a major factor in the carcinogenicity observed, prompting the FDA to halt further research of QS. In RTP, McConnell et al. (2010), and Haseman et al. (2015), using the authors' data, definitively determined the carcinogenicity to be secondary to necrosis and chronic inflammation. Decisions made in the design, conduct, analysis, interpretation and reporting in this study lack scientific foundation. This paper explores these decisions.

Quinacrine Ameliorates Cisplatin-Induced Renal Toxicity via Modulation of Sirtuin-1 Pathway.

Renal toxicity is a serious side effect that hinders the use of cisplatin, a commonly used and effective chemotherapeutic agent. Meanwhile, quinacrine is an FDA approved drug that has been stated for its anti-inflammatory effect. Thus, we investigated the ameliorative effect of quinacrine against cisplatin-induced renal toxicity. Single intraperitoneal (i.p.) 10 mg/kg cisplatin administration induced renal injury in rats. Our results showed that 10 mg/kg/day quinacrine decreased the mortality rate of rats from 46.15% (cisplatin group) to 12.5%, and significantly decreased renal tissue fibrosis, relative kidney to body weight ratio, serum creatinine and urea levels compared with the cisplatin group. Indeed, quinacrine significantly decreased renal malondialdehyde concentration and increased renal total antioxidant capacity, compared with the cisplatin group. Furthermore, quinacrine caused significant upregulation of renal sirtuin-1 (SIRT-1) with significant downregulation of intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor-α (TNF-α). Moreover, quinacrine significantly blocked cisplatin-induced apoptosis, which was made evident by downregulating renal apoptotic proteins (BAX and p53) and upregulating the renal anti-apoptotic protein BCL2, compared with the cisplatin group. In conclusion, this study demonstrates, for the first time, that quinacrine alleviates cisplatin-induced renal toxicity via upregulating SIRT-1, downregulating inflammatory markers (ICAM-1 and TNF-α), reducing oxidative stress, and inhibiting apoptosis.

Identification of compounds inhibiting prion replication and toxicity by removing PrPC from the cell surface.

The vast majority of therapeutic approaches tested so far for prion diseases, transmissible neurodegenerative disorders of human and animals, tackled PrPSc , the aggregated and infectious isoform of the cellular prion protein (PrPC ), with largely unsuccessful results. Conversely, targeting PrPC expression, stability or cell surface localization are poorly explored strategies. We recently characterized the mode of action of chlorpromazine, an anti-psychotic drug known to inhibit prion replication and toxicity by inducing the re-localization of PrPC from the plasma membrane. Unfortunately, chlorpromazine possesses pharmacokinetic properties unsuitable for chronic use in vivo, namely low specificity and high toxicity. Here, we employed HEK293 cells stably expressing EGFP-PrP to carry out a semi-automated high content screening (HCS) of a chemical library directed at identifying non-cytotoxic molecules capable of specifically relocalizing PrPC from the plasma membrane as well as inhibiting prion replication in N2a cell cultures. We identified four candidate hits inducing a significant reduction in cell surface PrPC , one of which also inhibited prion propagation and toxicity in cell cultures in a strain-independent fashion. This study defines a new screening method and novel anti-prion compounds supporting the notion that removing PrPC from the cell surface could represent a viable therapeutic strategy for prion diseases.