P53 Gene Expression and Nitric Oxide Levels after Artemisinin-Caffeine Treatment in Breast, Lungs and Liver of DMBA-Induced Tumorigenesis

OBJECTIVE

With increasing incidence of cancers globally and limited resources in some affected countries, repurposing existing drugs for reducing tumorigenesis is highly important. Artemisinin and caffeine have potent anti-oxidative and anti-tumor properties but are therapies for other diseases. This study evaluated the biochemical and p53 gene modulatory effects of doses of artemisinin-caffeine combination on breast, lungs and liver tissues in rats induced with DMBA.

METHODS

After due ethical approval, 30 animals were treated with 40mg/kg single dose of 7,12-dimethylbenzene anthracene (DMBA) as a model for DNA damage and induction of carcinogenesis. Five animals each received normal saline (normal), low dose artemisinin (Art; 4mg/kg), low dose caffeine (Caff; 25mg/kg), low dose combination of caff + art (25+4mg/kg), high dose combination of caff + art (50+8mg/kg) or no treatment (DMBA). All treatment doses were orally administered daily for two weeks post DMBA treatment. Nitric oxide levels and p53 relative gene expression was carried out using primer-specific RT-PCR, GAPDH was used as loading control and amplicons were resolved by gel electrophoresis.

RESULTS

DMBA induced lesions in breast, liver, and lung tissues evident from histology analysis, compared to normal group. In all 3 tissues, caffeine (25mg/kg) and combination of caff + art (25+4mg/kg) significantly reduced p53 gene expression (p < 0.05), but there was significant increase in the group treated with low dose art (4mg/kg) and high dose caff + art, which were similar to DMBA group (p<0.05). In lungs, nitric oxide (NO) increased in all groups but not in caffeine, in the liver NO decreased with caffeine or its combination with art, compared to DMBA group.

CONCLUSIONS

This study shows a dose-dependent synergistic anticancer effects of caffeine and artemisinin combination on p53 gene and nitric oxide regulation hence can mitigate tumor development.

In silico Structure Prediction, Molecular Docking, and Dynamic Simulation of Plasmodium falciparum AP2-I Transcription Factor

Plasmodium falciparum Apicomplexan Apetala 2 Invasion (PfAP2-I) transcription factor (TF) is a protein that regulates the expression of a subset of gene families involved in P. falciparum red blood cell (RBC) invasion. Inhibiting PfAP2-I TF with small molecules represents a potential new antimalarial therapeutic target to combat drug resistance, which this study aims to achieve. The 3D model structure of PfAP2-I was predicted ab initio using ROBETTA prediction tool and was validated using Save server 6.0 and MolProbity. Computed Atlas of Surface Topography of proteins (CASTp) 3.0 was used to predict the active sites of the PfAP2-I modeled structure. Pharmacophore modeling of the control ligand and PfAP2-I modeled structure was carried out using the Pharmit server to obtain several compounds used for molecular docking analysis. Molecular docking and postdocking studies were conducted using AutoDock vina and Discovery studio. The designed ligands' toxicity predictions and in silico drug-likeness were performed using the SwissADME predictor and OSIRIS Property Explorer. The modeled protein structure from the ROBETTA showed a validation result of 96.827 for ERRAT, 90.2% of the amino acid residues in the most favored region for the Ramachandran plot, and MolProbity score of 1.30 in the 98th percentile. Five (5) best hit compounds from molecular docking analysis were selected based on their binding affinity (between -8.9 and -11.7 Kcal/mol) to the active site of PfAP2-I and were considered for postdocking studies. For the absorption, distribution, metabolism, elimination, and toxicity (ADMET) properties, compound MCULE-7146940834 had the highest drug score (0.63) and drug-likeness (6.76). MCULE-7146940834 maintained a stable conformation within the flexible protein's active site during simulation. The good, estimated binding energies, drug-likeness, drug score, and molecular dynamics simulation interaction observed for MCULE-7146940834 against PfAP2-I show that MCULE-7146940834 can be considered a lead candidate for PfAP2-I inhibition. Experimental validations should be carried out to ascertain the efficacy of these predicted best hit compounds.

Abstract 5850: p53 gene expression and nitric oxide levels after artemisinin-caffeine treatment in breast, lungs and liver of DMBA-induced tumorigenesis

Background: With increasing incidence of cancers globally and limited resources in some affected countries, repurposing existing drugs for reducing tumorigenesis is highly important. Artemisinin and caffeine have potent anti-oxidative and anti-cancer properties, although they are therapies for other diseases. When p53 is activated, it repairs DNA damage, prevents tumorigenesis and induces apoptosis whereas nitric oxide is a pro-apoptotic modulator which can upregulate p53 thereby reducing tumorigenesis. We evaluated the biochemical and p53 gene modulatory effects of doses of artemisinin-caffeine combination on breast, lung and liver tumors in rats induced with DMBA.

Methods: After due ethical approval, 30 animals were treated with 40mg/kg single dose of 7,12-dimethylbenzene anthracene (DMBA) as a model for DNA damage and induction of carcinogenesis. Five animals each received low dose artemisinin (4mg/kg), low dose caffeine (25mg/kg), low dose combination of Art + Caff (4+25mg/kg), high dose combination of Art + Caff (8+50 mg/kg) or no treatment. All treatment doses were orally administered daily for two weeks post-DMBA treatment, normal control received saline. Nitric oxide levels were assessed and p53 relative gene expression was determined by primer-specific RT-PCR (GAPDH was used as loading control) and amplicons were resolved by gel electrophoresis.

Results: DMBA induced lesions in breast, liver, and lung tissues were evident from histology analysis, compared to untreated group. In all 3 tissues, low dose caffeine and combination of Art + Caff significantly reduced p53 gene expression (p &lt; 0.05), but there was significant increase in of p53 expression in low dose Art and high dose Art + Caff groups, which were similar to DMBA group (p&lt;0.05). There was also decrease in nitric oxide levels in treated groups compared to DMBA group.

Conclusions: This study shows a dose-dependent anticancer effects of caffeine and artemisinin combination on p53 gene and nitric oxide regulation and hence can mitigate against tumorigenesis.

Citation Format: Titilope M. Dokunmu, Sandra C. Opara, Omiete U. Awani. p53 gene expression and nitric oxide levels after artemisinin-caffeine treatment in breast, lungs and liver of DMBA-induced tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5850.

Hidden in plain sight: The effects of BCG vaccination in the COVID-19 pandemic

To investigate the relationship between Bacille Calmette‐Guérin (BCG) vaccination and SARS‐CoV‐2 by a bioinformatics approach, two datasets for the SARS‐CoV‐2 infection group and BCG‐vaccinated group were downloaded. Differentially Expressed Genes were identified. Gene ontology and pathways were functionally enriched, and networking was constructed in NetworkAnalyst. Lastly, the correlation between post‐BCG vaccination and COVID‐19 transcriptome signatures was established. A total of 161 DEGs (113 upregulated DEGs and 48 downregulated genes) were identified in the SARS‐CoV‐2 group. In the pathway enrichment analysis, a cross‐reference of upregulated Kyoto Encyclopedia of Genes and Genomes pathways in SARS‐CoV‐2 with downregulated counterparts in the BCG‐vaccinated group, resulted in the intersection of 45 common pathways, accounting for 86.5% of SARS‐CoV‐2 upregulated pathways. Of these intersecting pathways, a vast majority were immune and inflammatory pathways with top significance in interleukin‐17, tumor necrosis factor, NOD‐like receptors, and nuclear factor‐κB signaling pathways. Given the inverse relationship of the specific differentially expressed gene pathways highlighted in our results, the BCG‐vaccine may play a protective role against COVID‐19 by mounting a nonspecific immunological response and further investigation of this relationship is warranted.

Assessment of Toxicological Effects of Selected Popular Antidiabetic Drugs in Type II Diabetes Mellitus within Ota, Ogun State, Nigeria

Aim: The complications associated with diabetes and the new trend of using combination therapy in the management of the disease gave birth to this work, aimed at assessing the hepatotoxic and nephrotoxic effects of selected popularly used antidiabetic medications in type 2 diabetic patients within Ota, Ogun State, Nigeria. Study Design: The participants, diabetic (n=195) and non-diabetic (n=30) were divided into the following groups based on their medications: 1 (Non Diabetic control), 2 (Metformin), 3 (Glimepiride), 4 (Glibenclamide), 5 (Metformin and Glimepiride), 6 (Meformin and Glibenclamide), 7 (Metformin, Glimepiride and Glibenclamide) and 8 (Diabetic Dietary control). Methodology: Serum protein expression profiling, liver and kidney function parameters were assessed in participant’s blood using Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and standard laboratory methods respectively. Results: Glyceamic control within the diabetic groups was 29.23%. Urea concentration was significantly increased (p < 0.05) in groups 5 and 7 compared with groups 1 and 8 while the serum creatinine levels in the different groups showed no significant difference. Activities of alkaline phosphatase and aspartate aminotransferase increased significantly (p < 0.05) in group 5 compared with groups 1 and 8. A low molecular weight protein likely to be Leptin (molecular weight 18 kDa) was over-expressed in all the diabetic groups. Conclusion: This study shows that use of multiple rather than single drugs caused significant functional changes in the liver and kidney. The control of diabetes may best be carried out with dietary control and lifestyle modification as well as good therapeutic drug monitoring for safe assessment of baseline organ function.

Declining responsiveness of childhood Plasmodium falciparum infections to artemisinin-based combination treatments ten years following deployment as first-line antimalarials in Nigeria

Background

The development and spread of artemisinin-resistant Plasmodium falciparum malaria in Greater Mekong Subregion has created impetus for continuing global monitoring of efficacy of artemisinin-based combination therapies (ACTs). This post analyses is aimed to evaluate changes in early treatment response markers 10 years after the adoption of ACTs as first-line treatments of uncomplicated falciparum malaria in Nigeria.

Methods

At 14 sentinel sites in six geographical areas of Nigeria, we evaluated treatment responses in 1341 children under 5 years and in additional 360 children under 16 years with uncomplicated malaria enrolled in randomized trials of artemether-lumefantrine versus artesunate-amodiaquine at 5-year interval in 2009–2010 and 2014–2015 and at 2-year interval in 2009–2010 and 2012–2015, respectively after deployment in 2005.

Results

Asexual parasite positivity 1 day after treatment initiation (APPD1) rose from 54 to 62% and 2 days after treatment initiation from 5 to 26% in 2009–2010 to 2014–2015 (P = 0.002 and P <  0.0001, respectively). Parasite clearance time increased significantly from 1.6 days (95% confidence interval [CI]: 1.55–1.64) to 1.9 days (95% CI, 1.9–2.0) and geometric mean parasite reduction ratio 2 days after treatment initiation decreased significantly from 11 000 to 4700 within the same time period (P <  0.0001 for each). Enrolment parasitaemia > 75 000 μl^− 1, haematocrit > 27% 1 day post-treatment initiation, treatment with artemether-lumefantrine and enrolment in 2014–2015 independently predicted APPD1. In parallel, Kaplan-Meier estimated risk of recurrent infections by day 28 rose from 8 to 14% (P = 0.005) and from 9 to 15% (P = 0.02) with artemether-lumefantrine and artesunate-amodiaquine, respectively. Mean asexual parasitaemia half-life increased significantly from 1.1 h to 1.3 h within 2 years (P <  0.0001).

Conclusions

These data indicate declining parasitological responses through time to the two ACTs may be due to emergence of parasites with reduced susceptibility or decrease in immunity to the infections in these children.

Trial registration

Pan African Clinical Trial Registration PACTR201508001188143, 3 July 2015; PACTR201508001191898, 7 July 2015 and PACTR201508001193368, 8 July 2015 PACTR201510001189370, 3 July 2015; PACTR201709002064150, 1 March 2017; https://www.pactr.samrca.ac.za

Electronic supplementary material

The online version of this article (10.1186/s40249-019-0577-x) contains supplementary material, which is available to authorized users.

<p>Epidemiology of <em>Plasmodium falciparum</em> infection and drug resistance markers in Ota Area, Southwestern Nigeria</p>

Purpose: Effective routine monitoring and surveillance of parasite genes is a necessary strategy in the control of parasites’ resistance to antimalarial drugs, according to the WHO’s recommendation. This cross-sectional study therefore aimed at carrying out an epidemiological analysis on malaria incidence in Ado-Odo/Ota, Ogun State.

Patients and methods: Blood and corresponding saliva samples were collected from 1,243 subjects of all ages and sex presenting with fever and a parasitemia level ≥2,000 between September 2016 and March 2018. Samples were collected from selected health facilities in the study area of Ogun state to establish the prevalence of falciparum malaria and determine resistance genes harbored by the parasites. The overall prevalence of falciparum malaria in the study site by microscopic examination was 45.86%. The highest incidence of 57.42% was recorded among male subjects. Point mutations of K76T and N86Y in the Pfcrt and pfmdr-1 genes, as well as non-synonymous mutations in Pfk13 genes, were screened for and sequenced for further analysis.

Results:Pfcrt was detectable in 57.42% of blood and 51.02% of saliva samples, respectively. About 34.78% of the subjects that were confirmed microscopically harbored the Pfmdr-1 mutated gene while 26.67% of the saliva samples revealed Pfmdr-1. Epidemiological studies identified the presence of wild-type Pfk13 genes in 21.84% of blood and 44.44% of saliva samples correspondingly. For each of the genes evaluated, saliva portrayed great diagnostic performance when compared with blood.

Conclusion: Findings from this study have established the prevalence of malaria and the resistance pattern of P. falciparum in the study area. The findings may help in formulating drug policies and suggest the use of saliva as a noninvasive point-of-care method of diagnosing malaria potentially deployable to rural endemic areas.

Asymptomatic malaria infections and Pfmdr1 mutations in an endemic area of Nigeria

BACKGROUND

Malaria eradication globally is yet to be achieved and transmission is sustained in many endemic countries. Plasmodium falciparum continues to develop resistance to currently available anti-malarial drugs, posing great problems for malaria elimination. This study evaluates the frequencies of asymptomatic infection and multidrug resistance-1 (mdr-1) gene mutations in parasite isolates, which form the basis for understanding persistently high incidence in South West, Nigeria.

METHODS

A total of 535 individuals aged from 6 months were screened during the epidemiological survey evaluating asymptomatic transmission. Parasite prevalence was determined by histidine-rich protein II rapid detection kit (RDT) in healthy individuals. Plasmodium falciparum mdr-1 gene mutations were detected by polymerase chain reaction (PCR) followed by restriction enzyme digest and electrophoresis to determine polymorphism in parasite isolates. Sequencing was done to confirm polymorphism. Proportions were compared using Chi-square test at p value < 0.05.

RESULTS

Malaria parasites were detected by RDT in 204 (38.1%) individuals. Asymptomatic infection was detected in 117 (57.3%) and symptomatic malaria confirmed in 87 individuals (42.6%). Overall, individuals with detectable malaria by RDT was significantly higher in individuals with symptoms, 87 of 197 (44.2%), than asymptomatic persons; 117 of 338 (34.6%), p = 0.02. In a sub-set of 75 isolates, 18(24%) and 14 (18.6%) individuals had Pfmdr1 86Y and 1246Y mutations.

CONCLUSIONS

There is still high malaria transmission rate in Nigeria with higher incidence of asymptomatic infections. These parasites harbour mutations on Pfmdr1 which contribute to artemisinin partner drug resistance; surveillance strategies to reduce the spread of drug resistance in endemic areas are needed to eliminate the reservoir of malaria parasites that can mitigate the eradication of malaria in Nigeria.

Dataset on analysis of quality of health and social insurance subscription in different socio-economic class of workers in selected areas in southwest Nigeria

National social health insurance scheme aims to improve the health of citizens and provide equal access to health care across different income classes. This empirical datasets describes quality of health, insurance subscription, awareness, health care coverage and benefits in different socio-economic class of workers in Ota and Lagos, Nigeria. The perception of individual׳s state of health and level of satisfaction of accessed health care are reported and opinions on ways to meet the health needs of workers in a developing country such as Nigeria.

Evaluation of Plasmodium falciparum K13 gene polymorphism and susceptibility to dihydroartemisinin in an endemic area

Introduction: Plasmodium falciparum has developed resistance to artemisinin drugs in Southeast Asia, and its reduced sensitivity has been reported in other regions. This study aims to determine parasite susceptibility to the bioactive form of artemisinin derivatives- dihydroartemisinin (DHA)-, and to detect the K13 polymorphism in isolates from an endemic area of Nigeria. Methods: Ex-vivo response in 55 parasites isolates obtained from malaria-positive patients were exposed to pulse DHA concentration and cultured for 66 hours ex-vivo. Parasite ring stage survival (RSAex-vivo) relative to unexposed matched control was determined by microscopy, and parasite growth was compared using Mann-Whitney U-test at a significance level of P<0.05. The Kelch propeller gene was amplified using specific primers, then sequenced and analyzed for single nucleotide polymorphisms (SNPs), which were compared to reference PF3D7_1343700. Results: Overall, 151 of 375 (40.2%) individuals were positive during the study period. In 55 selected isolates, there was increased growth in unexposed wells but growth was inhibited in DHA-exposed wells, with growth rate between 14.9 – 96.7%. The mean RSAex-vivo value was 0.18 ± 0.09%, 95% CI (0.15-0.20). There was no significant mutation of the K13 gene in the parasite isolates evaluated. Conclusions: Plasmodium falciparum isolates from this endemic area show high sensitivity to dihydroartemisinin ex-vivo, with no mutations conferring artemisinin resistance. Continuous monitoring of parasite susceptibility to artemisinin combination drugs should be intensified to reduce chances of artemisinin resistance in endemic areas.

Artemisinin-induced delayed hemolysis after administration of artesunate and artesunate-amodiaquine in malaria-free Wistar rats

Background: Hemolysis is common in malaria infection and during the course of treatment. Previous studies have reported delayed post-artemisinin hemolysis occurring in naïve and immune individuals treated with parenteral or oral artemisinin-derivatives. This study aims to understand if delayed hemolysis occurs in the absence of malaria parasites and the underlying mechanisms for the hemolytic effects after administration of two antimalarial drugs to malaria-free Wistar rats. Methods: Forty animals were randomized into 5 groups of eight animals each; they received 4 mg/kg artesunate for 7 days (AS), 4 mg/kg artesunate plus 10mg/kg amodiaquine for 3 days (ASQ), 10mg/kg amodiaquine for 3 days (AQ), distilled water [normal control], (Control) and 1mg/kg phenylhydrazine for 1 day to induce hemolysis (PHZ) groups respectively. Packed cell volume (PCV), white blood cell differential count and serum haptoglobin (Hpt) levels were determined in all groups on day 4 and 18 to detect hemolysis. Mean values were compared using t-test and ANOVA with p values <0.05 taken to be significantly different. Results: Post-treatment mean PCV on day 4 was significantly lower than day 18 in all groups except AS group which had similar PCV all through evaluation. Although AQ had lowest mean PCV on day 4, by day 18, mean PCV returned to normal and hpt levels was significantly higher than AS and ASQ groups (p<0.001). Hpt level (mean ± sem) for AS, ASQ, AQ, and control on day 18 were: 18.67 ± 0.004, 50.66 ± 0.014, 73.06 ± 0.003, and 74.13 ± 0.032 mg/dl respectively (p < 0.0001). On day 18, AS and ASQ had significantly lower Hpt level compared to day 4 (p <0.001). No neutropenia was observed during the study. Conclusion: Artesunate induces delayed hemolysis in malaria-free animals possibly through an oxidative toxic effect on the red blood cell membrane. Delayed post-treatment hemolysis was not observed with artesunate-amodiaquine or amodiaquine alone.