Novel isoniazid-hydrazone derivatives induce cell growth inhibition, cell cycle arrest and apoptosis via mitochondria-dependent caspase activation and PI3K/AKT inhibition.

In this study, seven isoniazid-hydrazone derivatives (3a-g) were synthesized and their structures elucidated by chromatographic techniques, and then the antiproliferative effects of these compounds on various cancer cells were tested. The advanced anticancer mechanism of the most potent compound was then investigated. Antiproliferative activities of the synthesized compounds were evaluated on human breast cancer MCF-7, lung cancer A-549, colon cancer HT-29, and non-cancerous mouse fibroblast 3T3-L1 cell lines by XTT assay. Flow cytometry analysis were carried out to determine cell cycle distribution, apoptosis, mitochondrial membrane potential, multi-caspase activity, and expression of PI3K/AKT signaling pathway. The XTT results showed that all the title molecules displayed cytotoxic activity at varying strengths in different dose ranges, and among them, the strongest cytotoxic effect and high selectivity were exerted by 3d against MCF-7 cells with the IC50 value of 11.35 µM and selectivity index of 8.65. Flow cytometry results revealed that compound 3d induced apoptosis through mitochondrial membrane disruption and multi-caspase activation in MCF-7 cells. It also inhibited the cell proliferation via inhibition of expression of PI3K/AKT and arrested the cell cycle at G0/G1 phase. In conclusion, all these data disclosed that among the synthesized compounds, 3d is notable for in vivo anticancer studies.

Dual-centre evaluation of the FluoroType MTBDR version 2 assay for detection of Mycobacterium tuberculosis complex and resistance-conferring mutations in pulmonary and extrapulmonary samples from Denmark, Germany and Sierra Leone.

OBJECTIVES: We evaluated the ability of FluoroType MTBDR version 2 (FTv2; Hain Lifescience), a second-step real-time PCR assay, to simultaneously detect Mycobacterium tuberculosis complex (MTBC) DNA and mutations conferring resistance to rifampicin (RIF) and isoniazid (INH), in pulmonary and extrapulmonary samples from patients and compared them with corresponding cultures. METHODS: FTv2 MTBC was evaluated on 1815 and 432 samples from Denmark (DK) and Germany (DE), respectively. RIF and INH resistance mutations were assessed in the German samples and 110 samples from Sierra Leone and subsequently compared to phenotypic antimicrobial susceptibility testing and a composite reference DNA (CRD) based on the GenoType MTBDR line-probe assay and Sanger sequencing or whole-genome sequencing. RESULTS: Of the 584 (557 smear-negative) Danish and 277 (85 smear-negative) German sputum samples, 42 (16) and 246 (54) were culture positive, and 44 (18) and 222 (35) were FTv2 positive, providing an FTv2 sensitivity and specificity of 0.86 (0.63) and 0.98 (DK), 0.90 (0.65) and 1.00 (DE), respectively. The count, sensitivities, and specificities for all pulmonary samples were 1434, 0.79, and 0.99 (DK) and 347, 0.86, and 1.00 (DE), respectively; for extrapulmonary samples, 381, 0.33, 0.99 (DK) and 83, 0.50, and 1.00 (DE). The valid count, sensitivity, and specificity compared with CRD for detecting resistance mutations were RIF 355, 0.99, 0.96, and INH 340, 1.00, and 0.98, respectively. DISCUSSION: FTv2 reliably detects MTBC DNA in pulmonary and extrapulmonary samples and detects resistance mutations for INH and RIF resistance in inhA promoter, katG, and rpoB genes.

Isoniazide modified Ag nanoparticles triggered photothermal immunoassay for carcinoembryonic antigen detection.

As the most well-known analytical tool, the thermometer has been extended to the field of biological analysis based on the photothermal effect. Herein, isoniazide modified Ag nanoparticles were prepared as nanolabels to build an immunoassay. The nanoparticles were characterized by transmission electron microscope (TEM), dynamic laser scattering (DLS), X-ray powder diffraction (XRD), and Fourier transform infrared (FT-IR). When the target protein was present, the sandwich immunoassay was developed and the photothermal reaction was triggered by isoniazide modified Ag nanoparticles. As a reducing agent, isoniazide is used to transform phosphomolybdic acid hydrate into molybdenum blue solution. And molybdenum blue had good photothermal stability and high photothermal conversion efficiency. The temperature variation of molybdenum blue solution showed a positive correlation with the concentration of carcinoembryonic antigen (CEA). Thus, the target protein of CEA was quantitative detection by thermometer. The linear response range is 0.1 ng mL-1 to 40 ng mL-1, and the detection limit is 0.08 ng mL-1. Moreover, the proposed protocol had satisfactory selectivity, accuracy, and reproducibility.

Regulatory effect of PINK1/Parkin axis on mitophagy in isoniazide-induced hepatocellular injury. / PINK1/Parkin介导的线粒体自噬在异烟肼诱导的肝细胞损伤中的作用.

OBJECTIVES: Patients with tuberculosis, who are treated with long-term high-dose combined use of anti-tuberculosis drugs, can cause many adverse reactions such as liver damage, but the mechanism is still unclear. Although phosphatase and tensin homolog induced kinase 1 (PINK1)/Parkin axis might participate in the process of liver damage through regulating mitochondrial autophagy and oxidative stress in liver cells. However, the association between the mitochondrial autophagy regulated by the PINK1/Parkin axis and the liver injury induced by anti-tuberculosis drugs is unknown. This study aims to explore the mechanism of PINK1/Parkin signal axis in regulating hepatocellular injury induced by anti-tuberculosis drugs through mitochondrial autophagy, and to provide new therapeutic targets for the patients with liver damage caused by anti-tuberculosis drugs. METHODS: Mouse hepatocytes AML-12 were treated with isoniazide (INH) to induce liver injury. The mRNA and protein levels of PINK1, Parkin and autophagy associated factors were detected by real-time PCR and Western blotting in the normal AML-12 cells (control group), the AML-12 cells treated by INH (model group) and the AML-12 cells treated with INH and salidroside together (intervention group). Meantime, ELISA kit was used to detect the level of reactive oxygen species (ROS) in AML-12 cells, and the cell morphology and injury was observed by HE staining and transmission electron microscope (TEM). RESULTS: Compared with the control group, the mRNA (all P <0.01) and protein levels (all P <0.05) of PINK1, Parkin and microtubule associated protein 1 light chain 3 (LC3) were significantly decreased, the ubiquitination level was significantly decreased ( P <0.05), and the ROS level was increased ( P <0.05), and the hepatocellular cell showed obvious damage in the model group. Compared with the model group, the expression of PINK1, Parkin and LC3 were significantly increased in the intervention group (all P <0.05), as well as the ubiquitination level was also increased ( P <0.05). The ROS level mediated by mitochondria was decreased ( P <0.05). The results of HE staining and TEM showed that the cell status was improved and the damage of hepatocytes was significantly attenuated. CONCLUSIONS: In this study, the mechanism of mitochondrial autophagy mediated by PINK1/Parkin signal axis may be related to INH-induced injury in liver cells and it can regulate the damage state in vitro, indicating that Parkin is a potential molecular target for the prediction, diagnosis and treatment for liver injury induced by anti-tuberculosis drugs.

[Primary isoniazid preventive therapy : A strategy still relevant in the era of test and treat ; literature review]. / Chimioprophylaxie antituberculeuse primaire à l'isoniazide : une stratégie d'actualité à l'ère du tester et traiter ; revue de la littérature.

BACKGROUND: Tuberculosis remains a public health threat responsible as recently as 2018 for more than one million deaths. Chemoprophylaxis with isoniazid is one of the strategies implemented to control the disease. Although it is not yet widely prescribed, its utilization raises additional questions in the "test and treat" era of for anti-retroviral therapy. The objective of this study is to review the different randomized controlled trials of antitubercular Isoniazid Preventive Therapy (IPT). We have distinguished (a) "efficacy trials" (ET) comparing IPT to a placebo or the absence of chemoprophylaxis and (b) "IPT regimen trials" (RT) comparing IPT to one or several other regimens. METHODS: Literature search (keywords from published articles found in the Medline and Scopus data bases: "tuberculosis", "prophylaxis", "HIV", "randomized controlled trial") and standardized reading of selected articles reporting results from randomized trials of IPT in HIV-infected people. RESULTS: Eighteen selected trials (11 ET and 7 RT), including 19,725 participants. The regimens studied were 3H, 6H, 9H, 12H, 12H, 36H/2RZ, 3RH, 3RZ, 3RHZ, and 3HP [H: Isoniazid, R: Rifampicin, Z: Pyrazinamide, P: Rifapentine]. LOCATIONS: Ten in Africa, three in Haiti, one in India, one in the USA, one in the Americas and two multi-continental trials. In ET with or without antiretrovirals (ART), IPT significantly reduces the risk of tuberculosis, by 32 to 71%. In ET prior to ART, IPT does not appear to reduce mortality. In ET in patients receiving ART, on the other hand, IPT reduces mortality. As regards RT, there seems to be no reason to prefer other regimens to IPT. Tolerance is good. Importantly, IPT may reduce (rather than worsen) the risk of multidrug-resistant bacilli selection by decreasing the number of TB episodes and, consequently, the number of curative tuberculosis treatments. CONCLUSION: Far from becoming obsolete due to ARV treatment, IPT has remained a timely and relevant intervention.

[Screening and prevention of toxic optic neuropathies due to anti-mycobacterium therapies: proposal of recommendations]. / Dépistage et prévention des neuropathies optiques toxiques aux anti-mycobactériens : proposition de recommandations.

While treatment of pulmonary infections by Mycobacterium tuberculosis is currently only rarely the cause of iatrogenic complications, treatment of atypical mycobacterial infections often requires prolonged treatment duration, which can lead to toxic optic neuropathies. This review summarizes the indications for such prolonged treatment and risk factors for toxic optic neuropathies when using ethambutol, isoniazid and/or linezolid and proposes customized screening recommendations.

Quercetin modulates NRF2 and NF-κB/TLR-4 pathways to protect against isoniazid- and rifampicin-induced hepatotoxicity in vivo.

Isoniazid and rifampicin are crucial for treating tuberculosis (TB); however, they can cause severe hepatotoxicity leading to liver failure. Therapeutic options are limited and ineffective. We hypothesized that prophylaxis with quercetin attenuates isoniazid- and rifampicin-induced liver injury. We randomly divided Wistar rats into seven groups (n = 6). The animals received isoniazid and rifampicin or were co-treated with quercetin or silymarin for 28 days. The protective effect of quercetin was assessed using liver function tests and liver histology. Nuclear factor erythroid 2-related factor 2 (NRF2) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways were explored to elucidate the mechanism of action. Quercetin co-administration prevented the elevation of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and bilirubin compared with isoniazid and rifampicin treatment alone. In the histological analysis, we observed that quercetin prophylaxis lessened the severity of hepatic necrosis and inflammation compared with the anti-TB drug-treated group. Quercetin attenuated anti-TB drug-induced oxidative stress by increasing NRF2 activation and expression, boosting endogenous antioxidant levels. Additionally, quercetin blocked inflammatory mediators high mobility group box-1 (HMGB-1) and interferon γ (IFN-γ), inhibiting activation of the NF-κB/ toll like receptor 4 (TLR-4) axis. Quercetin protects against anti-TB liver injury by activating NRF2 and blocking NF-κB/TLR-4.

Naphthoquinone-based Hydrazone Hybrids: Synthesis and Potent Activity Against Cancer Cell Lines.

BACKGROUND: Natural naphthoquinones have shown diversified biological activities including antibacterial, antifungal, antimalarial, and cytotoxic activities. However, they are also compounds with acute cytotoxicity, immunotoxicity, carcinogenesis, and cardio- and hepatotoxicity, and the modification at their redox center is an interesting strategy to overcome such harmful activity. OBJECTIVE: In this study, four novel semisynthetic hydrazones, derived from the isomers α- and ß- lapachones (α and ß, respectively) and coupled with the drugs hydralazine (HDZ) and isoniazid (ACIL), were prepared, evaluated by electrochemical methods and assayed for anticancer activity. METHODS: The semisynthetic hydrazones were obtained and had their molecular structures established by NMR, IR, and MS. Anticancer activity was evaluated by cell viability determined by reduction of 3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H-tetrazolium bromide (MTT). The electrochemical studies, mainly cyclic voltammetry, were performed, in aprotic and protic media. RESULTS: The study showed that the compounds 2, 3, and 4 were active against at least one of the cancer cell lines evaluated, compounds 3 and 4 being the most cytotoxic. Toward HL-60 cells, compound 3 was 20x more active than ß-lapachone, and 3x more cytotoxic than doxorubicin. Furthermore, 3 showed an SI value of 39.62 for HL-60 cells. Compound 4 was active against all cancer cells tested, with IC50 values in the range 2.90-12.40 µM. Electrochemical studies revealed a profile typical of self-protonation and reductive cleavage, dependent on the supporting electrolyte. CONCLUSION: These results therefore indicate that compounds 3 and 4 are strong candidates as prototypes of new antineoplastic drugs.

Experiencia piloto con esquema rifapentina-isoniazida semanal por 3 meses para tratamiento de la infección tuberculosa latente en el Programa Nacional de Tuberculosis de Chile / Pilot experience with weekly rifapentine-isoniazid treatment for 3 months for latent tuberculosis infection at the Tuberculosis National Program of Chile

INTRODUCCIÓN: La prevención de la tuberculosis activa en los grupos de riesgo es clave para el control y eliminación de la tuberculosis. El tratamiento de la infección tuberculosa latente (TITL) con rifapentina e isoniazida en dosis semanales por 12 semanas es más corto que con otros esquemas, tiene menor hepatotoxicidad, mejor adherencia y es costo-efectivo. El OBJETIVO del estudio es evaluar la factibilidad de implementar este esquema a nivel programático en Chile. MÉTODOS: Se hizo una intervención piloto en territorios seleccionados entre mayo de 2018 y marzo de 2019. En esos territorios se reemplazó el esquema normado de TITL con isoniazida 6 meses por el esquema rifapentina-isoniazida 12 semanas. Además, se amplió la población objetivo, incluyendo a contactos mayores de 14 años. El tratamiento consistió en la administración conjunta de isoniazida y rifapentina por vía oral con frecuencia semanal, por 12 semanas, de forma supervisada por personal de salud. RESULTADOS: Ingresaron 238 pacientes al piloto, de los cuales 53% fueron mujeres y 54,2% fueron mayores de 14 años. Del total de pacientes, 203 (85,3%) completaron el tratamiento, 22 (9,2%) lo abandonaron, 8 (3,4%) presentaron reacciones adversas y 5 tuvieron otros motivos de egreso. CONCLUSIÓN: Tanto el TITL con rifapentinaisoniazida por 3 meses en dosis semanales supervisadas, como la incorporación de contactos adultos a TITL, son factibles de implementar a nivel programático en Chile.

INTRODUCTION: Prevention of active tuberculosis in risk groups is crucial in tuberculosis control and elimination. Treatment of latent tuberculosis (TITL) with rifapentine and isoniazid in weekly doses for 12 weeks is shorter than other pharmacological treatments, with less liver toxicity, better patient compliance and it is cost-effective. The OBJECTIVE of this study is to evaluate the feasibility to implement this treatment at a programmatic level in Chile. METHODS: A pilot intervention was conducted in selected territories between May 2018 and March 2019. Within these territories, the regulated treatment with isoniazid 6 months was replaced by the 12 weeks treatment with weekly rifapentine-isoniazide. Additionally, the target population was expanded to include contacts over 14 years old, currently not included in the national guidelines. Treatment consisted in oral administration of rifapentine and isoniazide together once a week for 12 weeks, under supervision of trained health workers. RESULTS: From 238 patients entered to the protocol, 53% of them were women and 54.2% were older than 14 years-old. Out of the total number of patients, 203 (85.3%) completed treatment, 22 (9.2%) abandoned, 8 (3.4%) had adverse drug reactions, and 5 ended treatment for different causes. CONCLUSION: Both TITL with rifapentine-isoniazide in 12 supervised weekly doses, and the inclusion of adult contacts in TITL, are feasible to implement at a programmatic level in Chile.

A novel mitochondria-targeted phosphorescence probe for hypochlorite ions detection in living cells.

Monitoring hypochlorite anion (ClO-) in living cells is particularly meaningful and valuable, because over-exposure of the ClO- may cause a potential health hazard towards animals and humans. Considering the special structure and properties of the gemini surfactant, a novel amphiphilic gemini-iridium complex Ir[(ppy-iso)2(bpy-tma2Br2)] (Ir-iso) with isoniazide as a recognition site for ClO- was designed. The Ir-iso possessed an excellent water-solubility as well as a strong ClO- binding capacity, as revealed from the rapid response of emission signal towards ClO-. It was worth noting that such probe had a highly-specific selectivity with a low detection limit (20.5 nM) and was suitable in physiological environment. The cell viability assay, cell imaging, and co-location studies further proved that the Ir-iso had little cytotoxicity and was specifically localized in the mitochondria of breast cancer cells, being a promising candidate of chemo-sensor to detect the endogenous ClO- in living cells.

Contact evaluation and isoniazid preventive therapy among close and household contacts of tuberculosis patients in Lima, Peru: an analysis of routine data.

OBJECTIVE: Contacts of pulmonary tuberculosis (TB) cases are at high risk of TB infection and progression to disease. Close and household contacts and those <5 years old have the highest risk. Isoniazid preventive therapy (IPT) can largely prevent TB disease among infected individuals. International and Peruvian recommendations include TB contact investigation and IPT prescription to eligible contacts. We conducted a study in Lima, Peru, to determine the number of close and household contacts who were evaluated, started on IPT, and who completed it, and the factors associated to compliance with national guidelines. METHODS: We conducted a longitudinal retrospective study including all TB cases diagnosed between January 2015 and July 2016 in 13 health facilities in south Lima. Treatment cards, TB registers and clinical files were reviewed and data on index cases (sex, age, smear status, TB treatment outcome), contact investigation (sex, age, kinship to the index case, evaluations at month 0, 2 and 6) and health facility (number of TB cases notified per year, proportion of TB cases with treatment success) were extracted. We tabulated frequencies of contact evaluation by contact and index case characteristics. To investigate determinants of IPT initiation and completion, we used generalised linear mixed models. RESULTS: A total of 2323 contacts were reported by 662 index cases; the median number of contacts per case was four (IQR, 2-5). Evaluation at month 0 was completed by 99.2% (255/257) of contacts <5 and 98.1% (558/569) of contacts aged 5-19 years. Of 191 eligible contacts <5 years old, 70.2% (134) started IPT and 31.4% (42) completed it. Of 395 contacts 5-19 years old, 36.7% (145) started IPT and 32.4% (47) completed it. Factors associated to not starting IPT among contacts <5 years old were being a second-degree relative to the index case (OR 6.6 95CI% 2.6-16.5), not having received a tuberculin skin test (TST) (OR 3.9 95%CI 1.4-10.8), being contact of a smear-negative index case (OR 5.5 95%CI 2.0-15.1) and attending a low-caseload health facility (OR 2.8 95%CI 1.3-6.2). Factors associated to not starting IPT among 5-19 year-olds were age (OR 13.7 95%CI 5.9-32.0 for 16-19 vs. 5-7 years old), being a second-degree relative (OR 3.0 95%CI 1.6-5.6), not having received a TST (OR 5.4, 95%CI 2.5-11.8), being contact of a male index case (OR 2.1 95CI% 1.2-3.5), with smear-negative TB (OR 1.9 95%CI 1.0-3.6), and attending a high-caseload health facility (OR 2.1 95%CI 1.2-3.6). Factors associated to not completing IPT, among contacts who started, were not having received a TST (OR 3.4 95%CI 1.5-7.9 for <5 year-olds, and OR 4.3 95%CI 1.7-10.8 for those 5-19 years old), being contact of an index case with TB treatment outcome other than success (OR 9.3 95%CI 2.6-33.8 for <5 year-olds and OR 15.3 95%CI 1.9-125.8 for those 5-19 years old), and, only for those 5-19 years old, attending a health facility with high caseload (OR 3.2 95%CI 1.4-7.7) and a health facility with low proportion of TB cases with treatment success (OR 4.4 95%CI 1.9-10.2). CONCLUSIONS: We found partial compliance to TB contact investigation, and identified contact, index case and health facility-related factors associated to IPT start and completion that can guide the TB programme in increasing coverage and quality of this fundamental activity.

OBJECTIF: Les contacts des cas de tuberculose (TB) pulmonaire présentent un risque élevé d'infection à la TB et d'évolution vers la maladie. Les contacts étroits et familiaux et ceux de moins de 5 ans sont les plus à risque. Le traitement préventif à l'isoniazide (TPI) peut largement prévenir la maladie TB chez les personnes infectées. Nous avons mené une étude à Lima, au Pérou, pour déterminer le nombre de contacts proches et familiaux qui ont été évalués, qui ont commencé le TPI et qui l'ont achevé, ainsi que les facteurs associés au respect des directives nationales. MÉTHODES: Etude longitudinal rétrospective de tous les cas de TB diagnostiqués entre janvier 2015 et juillet 2016 dans 13 établissements de santé dans le sud de Lima. Les cartes de traitement, les registres de TB et les dossiers cliniques ont été examinés et des données sur les cas indice, l'investigation des contacts et les établissements de santé ont été extraites. Nous avons tabulé les fréquences d'évaluation des contacts par les caractéristiques des contacts et des cas indice. Pour étudier les déterminants de l'initiation et de l'achèvement du TPI, nous avons utilisé des modèles linéaires mixtes généralisés. RÉSULTATS: Au total, 2.323 contacts ont été rapportés par 662 cas indice; 70,2% des contacts âgés de moins de 5 ans ont commencé le TPI et 31,4% l'ont terminé, tandis que 36,7% des contacts âgés de 5 à 19 ans ont commencé le TPI et 32,4% l'ont terminé. Les facteurs associés au fait de ne pas commencer ou de terminer le TPI étaient: être un parent de second degré du cas indice, ne pas avoir reçu le test tuberculinique, être le contact d'un cas indice à frottis négatif et fréquenter un établissement de santé à faible charge de travail pour les moins de cinq ans contre fréquenter un établissement de santé à charge de travail élevée pour les contacts plus âgés. CONCLUSIONS: Nous avons constaté une compliance partielle à l'enquête sur les contacts de la TB, et avons identifié les facteurs liés aux contacts, aux cas indice et aux établissements de santé associés au début et à la fin du TPI qui peuvent guider le programme de TB dans l'augmentation de sa couverture et de sa qualité.

Quercetin protected against isoniazide-induced HepG2 cell apoptosis by activating the SIRT1/ERK pathway.

Isoniazid (INH) is one of the most commonly used antituberculosis drugs, but its clinical applications have been limited by severe hepatic toxicity. Quercetin (Que), a natural flavonoid, has been proved to have many medicinal properties. This study aimed to clarify the possible protective effects of Que against INH-induced hepatotoxicity using HepG2 cells. Our results indicated that Que significantly increased cell viability, superoxide dismutase, and GSH levels, while decreased alanine aminotransferase/aspartate aminotransferase levels. Besides, Que significantly abrogated INH-induced cell apoptosis by upregulating the expression levels of Bcl-2 and decreasing the levels of Bax, cleaved caspase-3, and cleaved caspase-9. Furthermore, Que obviously reversed the inhibition of INH on Sirtuin 1 (SIRT1) expression and extracellular signal-regulated kinase (ERK) phosphorylation. Next, the SIRT1 inhibitor EX527 blocked the enhancement of Que upon ERK phosphorylation. Notably, EX527 partially abolished the beneficial effects of Que. In brief, our results provided the first evidence that Que protected against INH-induced HepG2 cells by regulating the SIRT1/ERK pathway.

Structure-based design of some isonicotinic acid hydrazide analogues as potential antitubercular agents.

New pyridine derivatives were designed and synthesized as Isonicotinic acid hydrazide (INH) analogues. The synthesized compounds were evaluated for their antitubercular activity against Mycobacterium tuberculosis strain H37Rv. Ten compounds (3c, 3e-g, 5a-c, 6h, 10 and 11b) showed promising antitubercular activity with MIC range 7.30 µM-19.39 µM. Compounds 3e, 3g, 5b and 11b were the most potent analogues, with MIC 7.30-8.74 µM. They were equipotent to the standard drug Ethambutol (MIC 7.64 µM) and more active than the standard drug Pyrazinamide (MIC 50.77 µM). They were further examined for cytotoxicity in human embryonic kidney (HEK) cell line at the concentration of 50 µg/mL using MTT assay. Results declared that most compounds showed acceptable safety margin. Molecular Docking studies into 2-trans-enoyl-acyl carrier protein reductase, called InhA have been conducted for compounds 3e, 3g, 5b and 11b using Molecular Operating Enviroment software (MOE 2016.0802), where reasonable binding interactions have been identified and effective overall docking scores have been recorded. Their drug-likeness has been assessed using Molinspiration and Osiris software.

Oxidative stress-mediated developmental toxicity induced by isoniazide in zebrafish embryos and larvae.

Isoniazide (INH) is an important first-line drug that is used to treat tuberculosis. However, the effect of INH on fetal growth has not yet been elucidated, and the mechanism of INH-induced developmental toxicity is still unknown. In the present study, we employed zebrafish embryos and larvae to investigate the developmental toxicity of INH. The survival rates of the embryos and larvae as well as the hatching rates of embryos were significantly reduced. Morphological abnormalities, including spinal curvature, yolk retention, swimming bladder absence, tail bending and shorter body lengths were induced by INH. Histopathological analysis showed loose cell-to-cell contacts and large vacuoles in the larval hepatocytes. Thin intestinal walls, frayed gut villi and widespread cell lysis were observed in the intestines of the larvae in the higher concentration (8, 16 mm) exposure groups. In addition, exposure to high doses (≥ 6 mm) of INH significantly reduced the locomotor capacity of the zebrafish larvae. INH significantly increased the levels of reactive oxygen species and malondialdehyde and decreased the superoxide dismutase activity in zebrafish larvae, which suggested that oxidative stress was induced and that the antioxidant capacity was inhibited. Superoxide dismutase 1 and liver fatty acid-binding protein mRNA levels were significantly downregulated, while the GSTP2 and cytochrome P450 3A mRNA levels were significantly upregulated in the INH-exposed zebrafish larvae. The overall results indicated that INH caused a dose- and time-dependent increase in developmental toxicity and that oxidative stress played an important role in the developmental toxicity induced by INH in zebrafish larvae. Copyright © 2017 John Wiley & Sons, Ltd.

[Current situation of primary prophylaxis with isoniazid (INH) in children who are contacts of patients with bacillary pulmonary tuberculosis in Abidjan (Cote d'Ivoire)]. / Situation actuelle de la chimioprophylaxie primaire à l'isoniazide (INH) chez les enfants contacts des patients atteints de tuberculose pulmonaire bacillifère à Abidjan (Côte d'Ivoire).

INTRODUCTION: The National tuberculosis program (NTP) in Ivory Coast recommends that children under 5 years living in a family environment with contagious tuberculosis patients, should receive Prophylactic treatment with INH (PTI), whatever the result of the tuberculin skin test (positive or negative) and their BCG status (vaccinated or not), at a dose of 5mg/kg/day for 6 months. We conducted this study to check the implementation of this recommendation in three support services of tuberculosis in Abidjan, the economic capital. MATERIAL AND METHOD: We conducted a multicenter, cross-sectional and descriptive study over 3 years (2011-2013), on consented patients, adolescents and adults aged at least 15 years, with a first episode of infectious pulmonary tuberculosis, in order to look for information on the INH prophylaxis in children under 5 years living under the same roof. We made patients interviews during their visit for bacteriological sputum controls at the second month of TB treatment. RESULTS: Of a total of 412 patients (53% males and 47% females) with a mean age of 34.5 years and with a low level of instruction (66.5%), we noticed 639 children under 5 years living under the same roof with them. Information on the screening of contact children was given to 71% of interviewed patients (291/412). Of the 339 children examined among 639 contacts, 234 (69%) had received only an intradermoreaction (IDR) and PTI was finally administered to 64% of them (217/339). CONCLUSION: High proportion of contact children under 5 not examined is a major concern for the NTP and a missed opportunity to prevent additional cases of tuberculosis among children.

Prevalence of Multidrug Resistant Pulmonary Tuberculosis in North Bihar.

INTRODUCTION: Multidrug resistant tuberculosis (MDR-TB) is caused by Infection with Mycobacterium tuberculosis which is resistant to both isoniazid (INH) and rifampicin (RIF), with or without any other anti tubercular drug. It is caused by resistant mutant strains due to inadequate treatment and poor compliance. Due to time taking conventional diagnostic methods, drug resistant strains continue to spread. Therefore rapid diagnosis and treatment of MDR-TB strains are prerequisites for the worldwide fight against TB. OBJECTIVE: To determine the prevalence of MDR TB in North Bihar by molecular diagnostic method and to facilitate early diagnosis and treatment. Also, to find out the number of those diagnosed cases who were successfully initiated the treatment in MDR TB Centre of DMCH. MATERIALS AND METHODS: This six month observational study was carried out in IRL Darbhanga, Damien TB research Centre of the Darbhanga Medical College and Hospital, Bihar, India. During the period of February-July 2014, 256 sputum samples were collected from suspected cases of multidrug resistant tuberculosis, from 6 districts of North Bihar around Darbhanga. These samples were subjected to routine microscopy and culture to detect Mycobacterium tuberculosis. Positive cases were subjected to drug sensitivity test by a molecular diagnostic method, Using Genotype MTBDR plus kit. RESULT: Out of 256 sputum samples from suspected cases of MDR TB, 122 cases were microscopy positive for tuberculosis. Among these 122 cases, tuberculosis was confirmed by PCR in 114 cases. Finally with the help of Line Probe Assay (LPA), 39(15%) samples were found to have resistance to both INH and Rifampicin. Male female ratio was 4:1. CONCLUSION: The Prevalence of Multi drug resistant pulmonary tuberculosis in North Bihar is 15%. It needs early diagnosis by molecular diagnostic method and prompt treatment to reduce the spread of MDR TB cases.

Inhibitory activity of isoniazid and ethionamide against Cryptococcus biofilms.

In recent years, the search for drugs to treat systemic and opportunistic mycoses has attracted great interest from the scientific community. This study evaluated the in vitro inhibitory effect of the antituberculosis drugs isoniazid and ethionamide alone and combined with itraconazole and fluconazole against biofilms of Cryptococcus neoformans and Cryptococcus gattii. Antimicrobials were tested at defined concentrations after susceptibility assays with Cryptococcus planktonic cells. In addition, we investigated the synergistic interaction of antituberculosis drugs and azole derivatives against Cryptococcus planktonic cells, as well as the influence of isoniazid and ethionamide on ergosterol content and cell membrane permeability. Isoniazid and ethionamide inhibited both biofilm formation and viability of mature biofilms. Combinations formed by antituberculosis drugs and azoles proved synergic against both planktonic and sessile cells, showing an ability to reduce Cryptococcus biofilms by approximately 50%. Furthermore, isoniazid and ethionamide reduced the content of ergosterol in Cryptococcus spp. planktonic cells and destabilized or permeabilized the fungal cell membrane, leading to leakage of macromolecules. Owing to the paucity of drugs able to inhibit Cryptococcus biofilms, we believe that the results presented here might be of interest in the designing of new antifungal compounds.

Mycobacterium tuberculosis enoyl-acyl carrier protein reductase inhibitors as potential antituberculotics: development in the past decade.

Mycobacterial enoyl-ACP-reductase, an enzyme contributing in mycolic acids biosynthesis, has been established as promising target of novel antimycobacterial drugs. The development of inhibitors active without previous activation by catalase/peroxidase system (e.g. isoniazid), seems to be rational approach. Catalase/peroxidase system is frequently responsible for resistance. We hereby present a review of direct mycobacterial enoyl-acyl carrier protein reductase inhibitors development in past decade. A special attention was paid to mechanism of inhibition, which shows relatively conserved interactions of inhibitors with Tyr 158 and cofactor. Hence, future developments of more effective antitubercular drugs should consider structural demands for potent direct mycobacterial enoyl reductase inhibitors.

Identification of drug-resistance gene type in Mycobacterium tuberculosis by gene chip in Hunan province / 国际检验医学杂志

Objective To investigate the drug resistance of 1 031 Mycobacterium tuberculosis to rifampicin and isoniazide in the Center Hospital of Changsha from January 1 ,2013 to September 30 ,2014 .Methods A total of 1 031 strains with positive culture result and identified as strains of Mycobacterium tuberculosis were used absolute concentration method to do the conventional drug susceptibility ,and detected rifampicin and isoniazide resistance gene including rpoB ,katG and inhA gene locus mutation by chip technology ,the results of two methods were compared using card square test statistics .Results By gene chip method ,the sensitive strain of rifampicin was 896 ,the drug-resistant strains was 135 ,the sensitive strains of isoniazide was 901 strains ,130 drug-resistant strains .Compared with the absolute concentration method ,resistance chip detection results were consistent with rifampicin resistant strains 1 011 strains(including 894 drug-resistant strains ,and 117 sensitive strains) ,the coincidence rate was 98 .00% ,consistent with isoniazideresistant strains 1 005 strains(including 890 drug-resistant strains ,115 sensitive strains) ,the coincidence rate was 97 .48% .The most common spot of rifampin resistance related mutations of rpoB gene was 531TCG to TTG ,accounted for 51 .11% ,followed by 526CAC→TAC ,accounted for 10 .37% ,11 strains with 526TCG to TTG ,accounted for 8 .15% .Isoniazid re-sistance was caused by mutations in katG315AGC→ACC resistant strains ,accounted for 83 .85% ,inhA-15C→T mutations accoun-ted for only 12 .30% .Conclusion The results of gene chip method is highly consistent with that of absolute concentration method , could be a fast and effective method for screening rifampicin and isoniazide ,the resistant gene of Mycobacterium tuberculosis to rif-ampicin and isoniazide almost mutate in rpoB531 ,526 and katG315 in Changsha .