Oxidative Stress and Hemoglobin Level of Complicated and Uncomplicated Malaria Cases among Children: A Cross-Sectional Study in Kumasi Metropolis, Ghana

Reduction of haemoglobin is related to metal mixtures exposure in Chinese preschoolers: Joint effect models

Heavy metal exposure is a known risk factor for hematologic disorders in children, yet the impact of co-exposure to multiple metals remains underexplored. This cross-sectional study investigates the relationship between urinary levels of 23 metals and haemoglobin (Hb) in 1460 Chinese preschoolers. The concentrations of the 23 urinary metals were quantified using an inductively coupled plasma mass spectrometer, while Hb levels were assessed through finger prick blood samples. To evaluate the co-exposure effects, we employed three approaches: Generalized linear regression model, joint effect models including Quantile g-Computation and Bayesian Kernel Machine Regression (BKMR). From the generalized linear regression and Quantile g-computation, urinary uranium, thallium, aluminium, iron and tungsten were correlated negatively with Hb, while urinary barium was correlated positively (all P < 0.05). Moreover, significant negative associations between metal mixtures exposure with Hb were identified in both Quantile g-computation [β (95% CI): -0.083 (-0.132, -0.033), P = 0.0012] and BKMR [90th percentile vs. 50th percentile β (95% CI): -0.238 (-0.368, -0.107), P < 0.001] with aluminium emerging as the primary contributor to this joint effect (weight in Quantile g-computation = 0.399, PIPs in BKMR = 0.896). These findings provide a potential explanation for environmental exposure to metals and Hb-related disease in preschoolers.

Malaria Is Associated with Diminished Levels of Ascorbic Acid: A Systematic Review and Meta-Analysis

Background: It is still unclear how ascorbic acid levels relate to the pathogenesis of malaria. This systematic review synthesized different ascorbic acid levels in malaria patients with different severity levels of malaria and Plasmodium species. Methods: The systematic review protocol was registered in the PROSPERO database (CRD42023394849). A systematic search of PubMed, Embase, MEDLINE, Ovid, Scopus, and Google Scholar was conducted to identify studies that reported ascorbic acid and malaria. The pooled standardized mean difference (Cohen's d) with 95% confidence intervals (CIs) was calculated using the random-effects model. Results: A total of 1480 articles were obtained from the searches of the databases, and 30 studies were included for syntheses. The meta-analysis revealed that patients with malaria had lower levels of ascorbic acid than those without malaria or uninfected controls (p < 0.01, Cohen's d = -3.71, 95% CI = -4.44 to -2.98, I2 = 98.87%, 30 studies). Comparable levels of ascorbic acid were observed between patients with severe malaria and those with nonsevere malaria (p = 0.06, Cohen's d = -1.39, 95% CI = -2.85 to 0.07, I2 = 96.58%, 4 studies). Similarly, levels of ascorbic acid were comparable between patients with Plasmodium falciparum and Plasmodium vivax malaria (p = 0.34, Cohen's d = -1.06, 95% CI = -3.23 to 1.12, I2 = 97.30%, 3 studies). Conclusions: The meta-analysis reveals diminished levels of ascorbic acid in malaria cases. Manipulating the host's nutritional status, such as by supplementing it with ascorbic acid to restore reactive oxygen species balance, may alter the progression of malarial infection and prevention of disease severity. Antioxid. Redox Signal. 40, 460-469.

Oxidative Stress in Parasitic Diseases-Reactive Oxygen Species as Mediators of Interactions between the Host and the Parasites

Oxidative stress plays a significant role in the development and course of parasitic infections, both in the attacked host organism and the parasite organism struggling to survive. The host uses large amounts of reactive oxygen species (ROS), mainly superoxide anion (O2•-) and hydrogen peroxide (H2O2), to fight the developing parasitic disease. On the other hand, the parasite develops the most effective defense mechanisms and resistance to the effects of ROS and strives to survive in the host organism it has colonized, using the resources and living environment available for its development and causing the host's weakening. The paper reviews the literature on the role of oxidative stress in parasitic diseases, which are the most critical epidemiological problem worldwide. The most common parasitosis in the world is malaria, with 300-500 million new cases and about 1 million deaths reported annually. In Europe and Poland, the essential problem is intestinal parasites. Due to a parasitic infection, the concentration of antioxidants in the host decreases, and the concentration of products of cellular components oxidation increases. In response to the increased number of reactive oxygen species attacking it, the parasites have developed effective defense mechanisms, including primarily the action of antioxidant enzymes, especially superoxide dismutase and nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)-dependent complexes glutathione and thioredoxin.

Efficacy of artesunate combined with Atractylodes lancea or Prabchompoothaweep remedy extracts as adjunctive therapy for the treatment of cerebral malaria

BACKGROUND

Cerebral malaria is one of the most serious complications of Plasmodium infection and causes behavioral changes. However, current antimalarial drugs have shown poor outcomes. Therefore, new antimalarials with neuroprotective effects are urgently needed. This study aimed to evaluate the effects of selected extracts as monotherapy or adjunctive therapy with artesunate on antimalarial, anti-inflammatory, antioxidant, and neuroprotective properties in experimental cerebral malaria (ECM).

METHODS

ECM was induced in male C57BL/6 mice by infection with Plasmodium berghei ANKA (PbA). Ethanolic extracts of Atractylodes lancea (a dose of 400 mg/kg) and Prabchompoothaweep remedy (a dose of 600 mg/kg) were evaluated as monotherapy and adjunctive therapy combined with artesunate at the onset of signs of cerebral malaria and continued for 7 consecutive days. Parasitemia, clinical scores, and body weight were recorded throughout the study. At day 13 post-infection, mouse brains were dissected and processed for the study of the inflammatory response, oxidative stress, blood-brain barrier (BBB) integrity, histopathological changes, and neurocognitive impairments.

RESULTS

Ethanolic extracts of A. lancea and Prabchompoothaweep remedy alone improved cerebral malaria outcome in ECM, whereas artesunate combined with extracts of A. lancea or Prabchompoothaweep remedy significantly improved the outcome of artesunate and crude extracts alone. Using real-time PCR, PbA-infected mice that had received the combination treatment showed significantly reduced gene expression of inflammatory cytokines (TNF-α, IL-1β, IL-6, and IL-10), chemokines (CXCL4 and CXCL10), and adhesion molecules (ICAM-1, VCAM1, and CD36). The PbA-infected mice that received the combination treatment showed a significantly decreased malondialdehyde level compared to the untreated group. Similarly, the Evans blue dye assay revealed significantly less dye extravasation in the brains of infected mice administered the combination treatment, indicating improved BBB integrity. Combination treatment improved survival and reduced pathology in the PbA-infected group. Additionally, combination treatment resulted in a significantly reduced level of cognitive impairment, which was analyzed using a novel object recognition test.

CONCLUSIONS

This study demonstrated that artesunate combined with A. lancea or Prabchompoothaweep remedy extracts as adjunctive therapy reduced mortality, neuroinflammation, oxidative stress, BBB integrity protection, and neurocognitive impairment in the ECM.

Increased Blood Concentrations of Malondialdehyde in Plasmodium Infection: A Systematic Review and Meta-Analysis

Several studies have evaluated the relationship between malondialdehyde (MDA) concentrations and Plasmodium infections; however, the findings remain inconclusive. This study synthesized differences in MDA concentrations among patients with different levels of clinical severity, uninfected controls, and different Plasmodium species. The research protocol was registered in PROSPERO (CRD42023393540). Systematic literature searches for relevant studies were performed using the Embase, MEDLINE, Ovid, ProQuest, PubMed, Scopus, and Google Scholar databases. Qualitative and quantitative syntheses (meta-analyses) of distinct MDA concentrations between the disease groups were performed. Twenty-three studies met the eligibility criteria and were included in the systematic review. Overall, MDA concentrations were significantly elevated in participants with malaria relative to uninfected controls (p < 0.01, Cohen d: 2.51, 95% confidence interval (CI): 1.88-3.14, I2: 96.22%, 14 studies). Increased MDA concentrations in participants with malaria compared with uninfected controls were found in studies that enrolled patients with P. falciparum malaria (p < 0.01, Cohen d: 2.50, 95% CI: 1.90-3.10, I2: 89.7%, 7 studies) and P. vivax malaria (p < 0.01, Cohen d: 3.70, 95% CI: 2.48-4.92, I2: 90.11%, 3 studies). Our findings confirm that MDA concentrations increase during Plasmodium infection, indicating a rise in oxidative stress and lipid peroxidation. Thus, MDA levels can be a valuable biomarker for evaluating these processes in individuals with malaria. However, further research is necessary to fully elucidate the intricate relationship between malaria, antioxidants, oxidative stress, and the specific role of MDA in the progression of malaria.

Impact of Oxidative Stress on Risk of Death and Readmission in African Children With Severe Malaria: A Prospective Observational Study

BACKGROUND

We hypothesized that oxidative stress in Ugandan children with severe malaria is associated with mortality.

METHODS

We evaluated biomarkers of oxidative stress in children with cerebral malaria (CM, n = 77) or severe malarial anemia (SMA, n = 79), who were enrolled in a randomized clinical trial of immediate vs delayed iron therapy, compared with community children (CC, n = 83). Associations between admission biomarkers and risk of death during hospitalization or risk of readmission within 6 months were analyzed.

RESULTS

Nine children with CM and none with SMA died during hospitalization. Children with CM or SMA had higher levels of heme oxygenase-1 (HO-1) (P < .001) and lower superoxide dismutase (SOD) activity than CC (P < .02). Children with CM had a higher risk of death with increasing HO-1 concentration (odds ratio [OR], 6.07 [95% confidence interval {CI}, 1.17-31.31]; P = .03) but a lower risk of death with increasing SOD activity (OR, 0.02 [95% CI, .001-.70]; P = .03). There were no associations between oxidative stress biomarkers on admission and risk of readmission within 6 months of enrollment.

CONCLUSIONS

Children with CM or SMA develop oxidative stress in response to severe malaria. Oxidative stress is associated with higher mortality in children with CM but not with SMA.

CLINICAL TRIALS REGISTRATION

NCT01093989.

Oxidative stress and associated clinical manifestations in malaria and sickle cell (HbSS) comorbidity

In Ghana, uncomplicated malaria and sickle cell disease (SCD) is common, hence comorbidity is not farfetched. However, the extent of oxidative stress and the array of clinical manifestations in this comorbidity (presence of both malaria and SCD) has not been fully explored. This study highlights the impact of uncomplicated malaria on SCD. The level of isoprostane, 8-iso-prostaglandin F2α (8-iso-PGF2α) was used to assess oxidative stress while plasma biochemistry and urinalysis was used to assess renal function. Hematological profiling was also done to assess the impact of comorbidity on the hematological cell lines. Of the 411 study participants with malaria, 45 (11%) had SCD. Mean body temperature was significantly higher in comorbidity compared to malaria and SCD cohorts, while a lower parasite density range was obtained in comorbidity compared to malaria cohorts. Furthermore, in comorbidity, the 8-iso-PGF2α oxidative stress biomarker was significantly elevated in all ages, parasite density ranges and gender groups. Comorbidity affected both leukocytic and erythrocytic cell lines with significant eosinophilia and monocytosis coexisting with erythrocytic parameters consistent with severe anemia. Biochemically, while plasma creatinine and bilirubin were significantly elevated in comorbidity, spot urinary creatinine was significantly reduced. Additionally, urine samples in the comorbid state were slightly acidic and hypersthenuric with significant hematuria, proteinuria, and bilirubinemia. Finally, 80% or more malaria-SCD presented with chills, fever, anorexia, headache, joint pains, lethargy, and vomiting. In conclusion, malaria could induce vaso-occlusive crisis in sickle cell disease, therefore, prompt management will alleviate the severity of this comorbidity.

Oxidative Stress in Malaria: Potential Benefits of Antioxidant Therapy

Malaria is an infectious disease and a serious public health problem in the world, with 3.3 billion people in endemic areas in 100 countries and about 200 million new cases each year, resulting in almost 1 million deaths in 2018. Although studies look for strategies to eradicate malaria, it is necessary to know more about its pathophysiology to understand the underlying mechanisms involved, particularly the redox balance, to guarantee success in combating this disease. In this review, we addressed the involvement of oxidative stress in malaria and the potential benefits of antioxidant supplementation as an adjuvant antimalarial therapy.

Anti-Malarial and Anti-Lipid Peroxidation Activities of Deferiprone-Resveratrol Hybrid in Plasmodium berghei-Infected Mice

Simple Summary

Malaria remains a public health problem in tropical and subtropical countries. The emergence of malaria parasite resistance to antimalarial drugs has been recently considered a serious issue. Alternative compounds have become an important therapeutic strategy to achieve malaria treatment. Iron chelators are widely used for the treatment of iron overload patients. The iron chelators also reveal an inhibitory effect on malaria parasite growth by depriving the parasite intracellular iron. This study presented the potential of the novel hybrid iron chelator, deferiprone-resveratrol hybrid on the inhibition of malaria parasite growth, the improvement of hematological parameters and the alleviatation of oxidative tissue damage in malaria-infected mice. Deferiprone-resveratrol hybrid would be used as a therapeutic/preventive compound to increase the efficacy of treatment and eliminate an antimalarial drug resistance.

Abstract

Iron is essential for all organisms including fast-dividing malarial parasites. Inversely, iron chelators can inhibit parasite growth through the inhibition of DNA synthesis and can ameliorate oxidative cell damage. Deferiprone (DFP)-resveratrol (RVT) hybrid (DFP-RVT) is a lipophilic anti-oxidative, iron-chelating agent that has displayed potent neuroprotective and anti-plasmodium activities in vitro. The goal of this work was to investigate the inhibitory effects of DFP-RVT on parasite growth and oxidative stress levels during malaria infections. Mice were intraperitoneally infected with P. berghei and orally administered with DFP, DFP-RVT and pyrimethamine for 4 d. The percentage of parasitemia was determined using Giemsa’s staining/microscopic examination. Amounts of the lipid-peroxidation product, thiobarbituric acid-reactive substance (TBARS), were determined in both plasma and liver tissue. In our findings, DFP-RVT exhibited a greater potent inhibitory effect and revealed an improvement in anemia and liver damage in infected mice than DFP. To this point, the anti-malarial activity was found to be associated with anti-RBC hemolysis and the liver weight index. In addition, plasma and liver TBARS levels in the DFP-RVT-treated mice were lower than those in DFP-treated mice. Thus, DFP-RVT could exert anti-plasmodium, anti-hemolysis and anti-lipid peroxidation activities to a better degree than DFP in P. berghei-infected mice.

Expression of 4-Hydroxynonenal (4-HNE) and Heme Oxygenase-1 (HO-1) in the Kidneys of Plasmodium berghei-Infected Mice

Acute kidney injury (AKI) is one of the most serious complications of severe Plasmodium falciparum malaria, but the exact pathogenic mechanisms of AKI in P. falciparum infection have not been clearly elucidated. We hypothesized that oxidative stress is a potential mediator of acute tubular necrosis in P. falciparum-infected kidneys. Therefore, this study aimed to investigate the histopathological changes and markers of oxidative stress in kidney tissues from mice with experimental malaria. DBA/2 mice were divided into two groups: the mice in the malaria-infected group (n = 10) were intraperitoneally injected with 1 × 10⁶P. berghei ANKA-infected red blood cells, and the mice in the control group (n = 10) were intraperitoneally injected with a single dose of 0.85% normal saline. Kidney sections were collected and used for histopathological examination and the investigation of 4-hydroxynonenal (4-HNE) and heme oxygenase-1 (HO-1) expression through immunohistochemistry staining. The histopathology study revealed that the P. berghei-infected kidneys exhibited a greater area of tubular necrosis than those of the control group (p < 0.05). The positive staining scores for 4-HNE and HO-1 expression in tubular epithelial cells of the P. berghei-infected group were significantly higher than those found for the control group (p < 0.05). In addition, significant positive correlations were found between the tubular necrosis score and the positive staining scores for 4-HNE and HO-1 in the kidneys from the P. berghei-infected group. In conclusion, this finding demonstrates that increased expression of 4-HNE and HO-1 might be involved in the pathogenesis of acute tubular damage in the kidneys during malaria infection. Our results provide new insights into the pathogenesis of malaria-associated AKI and might provide guidelines for the future development of a therapeutic intervention for malaria.

Evaluation of red blood cell count as an ancillary index to hemoglobin level in defining the severe falciparum malarial anemia among Ghanaian children in low-resource communities

Our study evaluated red blood cell count as supporting hematological index to hematocrit level in predicting severe malarial anemia instead of the hemoglobin levels among malaria-infected children in Ghana. This case-control study was conducted at the Komfo Anokye Teaching Hospital (KATH) in Kumasi, Ghana. The study recruited 139 children, of which 45 were Controls (C), 43 with severe malaria (SM), and 51 with mild malaria (MM). Validated questionnaires were administered to obtain the socio-demographic data from each respondent. Venous blood was obtained for parasitemia count and to determine the hematological profile of each participant. With point of observation, data analysis was done. The mean age of the children was 4.22 ± 2.65 years. Median levels of hemoglobin (Hb) decreased in the order; C > MM > SM (P < 0.0001). There was a reduction in median levels of hematocrit (HCT) (P < 0.0001), RBC (red blood cells count) (<0.0001), from the MM to the SM. Among patients with severe malaria, there were a positive significant spearmen's co-efficient correlations between median levels of RBC (r = 0.652, P = 0.005) and HB (r = 0.640, P = 0.006) individually against HCT. However among the mild malaria patients only RBC (r = 0.884, P < 0.001) was positively correlated against HCT. At a cut-off of <4.0×10⁶/uL for RBC and <8.8 g/dL for Hb, RBC (90.4%) recorded a slightly high accuracy in predicting severe falciparum malarial anemia than Hb (86.9%) among the cases. Red blood cell count may be a promising indicator to support hematocrit (<15%) in defining severe malarial anemia than hemoglobin level (<5 g/dL) among malaria-infected children from endemic areas in Ghana.