Chemokine, cytokine and haematological profiles in Sprague-Dawley rats co-infected with Plasmodium berghei ANKA and Trichinella zimbabwensis-A laboratory animal model for malaria and tissue-dwelling nematodes co-infection

A systematic review of circulating IP-10/CXCL10 in patients with Plasmodium infections in relation to disease severity

Interferon γ-induced protein 10 kDa (IP-10) or C-X-C motif chemokine 10 (CXCL10) is produced and secreted from specific leukocytes such as neutrophils, eosinophils, and monocytes, which play key roles in the immune response to Plasmodium infections. This systematic review aimed to collate and critically appraise the current evidence on IP-10 levels in malaria patients. It provided insights into its role in malaria pathogenesis and potential as a biomarker for Plasmodium infections and disease severity. The protocol for this systematic review was registered in PROSPERO (number CRD42024556087). A comprehensive literature search was conducted across multiple databases, including Embase, PubMed, Scopus, Ovid, ProQuest, and MEDLINE, to identify relevant studies examining the role of IP-10 in patients with Plasmodium infections. A narrative synthesis was applied to summarize key findings and to provide an overview of the relationship between IP-10/CXCL10 levels and Plasmodium infection and disease severity. A total of 1933 records were identified, and 26 studies were included in the synthesis. The studies collectively indicated that IP-10 levels are elevated in patients with Plasmodium infections compared to healthy or non-malarial controls. Most studies reported that increased IP-10 levels were associated with increased disease severity. However, a few studies found no significant difference or decreased levels in patients with severe Plasmodium infections compared to those with uncomplicated or mild malaria. Additionally, several studies indicated that IP-10 levels were elevated in cerebral malaria. The systematic review suggests that IP-10 is elevated in patients with Plasmodium infections. However, the variability in findings across different studies regarding the association between IP-10 and severe malaria, particularly cerebral malaria, highlights the need for further comprehensive studies. Addressing confounding factors will be crucial in future research to better understand the role of IP-10 in Plasmodium infections and the pathogenesis of severe disease.

Prior Trichinella spiralis infection protects against Schistosoma mansoni induced hepatic fibrosis

Background

Schistosomiasis affects approximately 250 million people worldwide, with 200,000 deaths annually. It has been documented that the granulomatous response to Schistosoma mansoni (S. mansoni) oviposition is the root cause of progressive liver fibrosis in chronic infection, in 20% of the patients, and can lead to liver cirrhosis and/or liver cancer. The influence of helminths coinfection on schistosomiasis-induced liver pathological alterations remains poorly understood. Therefore, in this study, we investigated the effect of Trichinella spiralis (T. spiralis) infection on S. mansoni-induced hepatic fibrosis.

Materials and methods

Thirty adult male Balb-c mice were divided into three groups. Group 1 was left uninfected; group 2 was infected with S. mansoni cercariae and group 3 was orally infected with T. spiralis larvae, then 28 days later, this group was infected with S. mansoni cercariae. All groups were sacrificed at the end of the 8th week post infection with S. mansoni to evaluate the effect of pre-infection with T. spiralis on S. mansoni induced liver fibrosis was evaluated parasitologically (worm burden and egg count in tissues), biochemically (levels of alanine aminotransferase and aspartate aminotransferase), histopathologically (H&E and MT staining, and immunohistochemical staining for the expression of α-SMA, IL-6, IL-1β, IL-17, IL-23, TNF-α, and TGF-β).

Results

The results in the present study demonstrated marked protective effect of T. spiralis against S. mansoni induced liver pathology. We demonstrated that pre-infection with T. spirais caused marked reduction in the number of S. mansoni adult worms (3.17 ± 0.98 vs. 18 ± 2.16, P = 0.114) and egg count in both the intestine (207.2 ± 64.3 vs. 8,619.43 ± 727.52, P = 0.009) and liver tissues (279 ± 87.2 vs. 7,916.86 ± 771.34; P = 0.014). Consistently, we found significant reductions in both number (3.4 ± 1.1 vs. 11.8.3 ± 1.22; P = 0.007) and size (84 ± 11 vs. 294.3 ± 16.22; P = 0.001) of the hepatic granulomas in mice pre-infected with T. spiralis larvae compared to those infected with only S. mansoni. Furthermore, pre- infection with T. spiralis markedly reduced S. mansoni- induced hepatic fibrosis, as evidenced by decreased collagen deposition, low expression of α-SMA, and significantly reduced levels of IL-17, IL-1B, IL-6, TGF-B, IL-23, and TNF-α compared to mice infected with S. mansoni only.

Conclusions

Our data show that pre-infection with T. spiralis effectively protected mice from severe schistosomiasis and liver fibrosis. We believe that our findings support the potential utility of helminths for the preventing and ameliorating severe pathological alterations induced by schistosomiasis.

Effect of black seeds (Nigella sativa) on inflammatory and immunomodulatory markers in Plasmodium berghei-infected mice

Nigella sativa, a core dietary supplement and food additive in folklore is one of the most broadly studied seed plants in the global nutraceutical sector. Malaria infection impairs the ability of principal cells of the immune system to trigger an efficient inflammatory and immune response. Ninety-six mice, weighing 20-25 g, were grouped into 12 consisting of 8 animals each. The mice were infected with standard inoculum of the strain NK65 Plasmodium berghei (chloroquine sensitive) and the percentage parasitemia suppression were evaluated. The individual effect of black seed supplemented diet and its combinatory effect with chloroquine (CQ) were investigated on reactive oxygen species (ROS), glutathione peroxidase (GPx), reduced glutathione (GSH), glutathione-S-transferase (GST), serum immunoglobulins (IgG and IgM), and the hematological parameters (hemoglobin, packed cell volume, and red blood cell count) in P. berghei infected mice. The inflammatory cytokines, tumor necrosis factor (TNF-α), interleukin (IL-6 and IL-10), as well as IgG and IgM were assayed in the serum. The mice temperature and behavioral changes were observed. Infected mice treated with the dietary supplementation of black seed with a percentage inclusion (2.5%, 5%, 10%) showed significantly decreased parasitemia and ROS levels (p < 0.05) compared with the untreated mice. The result demonstrated a significant suppression in the pro-inflammatory cytokines (TNF-α, IL-6) levels and a notable elevation in the anti-inflammatory cytokine (IL-10), antioxidant markers as well as the immunoglobulin levels of the P. berghei-infected mice treated with black seed. The study revealed that black seed enhanced host antioxidant status, modulated inflammatory and immune response by regulating some inflammatory cytokines and immunomodulatory mediators. PRACTICAL APPLICATIONS: Black seed (Nigella sativa) has been a dietary supplement and natural remedy for many centuries. Inflammatory and immune diseases are the most notable cause of mortality in the world and more than 50% of deaths have been attributed to it. However, there is paucity of information on the effect of N. sativa on anti-inflammatory and immunomodulatory ability during malaria infection. The result suggests that N. sativa produced antioxidant, anti-inflammatory, and immunomodulatory effect in Plasmodium berghei-infected mice via the participation of glutathione antioxidant system, serum antibodies, and some inflammatory cytokines.

Cytokines, Chemokines, Insulin and Haematological Indices in Type 2 Diabetic Male Sprague Dawley Rats Infected with Trichinella zimbabwensis

Diabetes mellitus is a chronic metabolic disease induced by the inability to control high blood glucose level. Helminth-induced immunomodulation has been reported to prevent or delay the onset of type 2 diabetes mellitus (T2DM), which, in turn, ameliorates insulin sensitivity. Therefore, there is a need to understand the underlying mechanisms utilized by helminths in metabolism and the induction of immuno-inflammatory responses during helminthic infection and T2DM comorbidity. This study aimed at using a laboratory animal model to determine the cytokines, chemokines and haematological indices in diabetic (T2DM) male Sprague Dawley (SD) rats infected with Trichinella zimbabwensis. One hundred and two male SD rats (160–180 g) were randomly selected into three experimental groups (i. T2DM-induced group (D) ii. T. zimbabwensis infected + T2DM group (TzD) and iii. T. zimbabwensis-infected group (Tz)). Rats selected for the D group and TzD group were injected with 40 mg/kg live weight of streptozotocin (STZ) intraperitoneally to induce T2DM, while animals in the Tz and TzD group were infected with T. zimbabwensis. Results showed that adult T. zimbabwensis worm loads and mean T. zimbabwensis larvae per gram (lpg) of rat muscle were significantly higher (p < 0.001) in the Tz group when compared to the TzD group. Blood glucose levels in the D group were significantly higher (p < 0.001) compared to the TzD group. An increase in insulin concentration was observed among the TzD group when compared to the D group. Liver and muscle glycogen decreased in the D when compared to the TzD group. A significant increase (p < 0.05) in red blood cells (RBCs) was observed in the D group when compared to the TzD and Tz groups. An increase in haematocrit, haemoglobin, white blood cells (WBCs), platelet, neutrophils and monocyte were observed in the D group when compared to the TzD group. TNF-α, IFN-γ, IL-4, IL-10 and IL-13 concentrations were elevated in the TzD group when compared to the D and Tz groups, while IL-6 concentration showed a significant reduction in the Tz when compared to the D and the TzD groups. A significant increase in CCL5 in the D and TzD groups was observed in comparison to the Tz group. CXCL10 and CCL11 concentration also showed an increase in the TzD group in comparison to the Tz and the D groups. Overall, our results confirm that T. zimbabwensis, a parasite which produces tissue-dwelling larvae in the host, regulates T2DM driven inflammation to mediate a positive protective effect against T2DM outcomes.

Blood glucose, insulin and glycogen profiles in Sprague-Dawley rats co-infected with Plasmodium berghei ANKA and Trichinella zimbabwensis

Background

Plasmodium falciparum and tissue dwelling helminth parasites are endemic in sub-Saharan Africa (SSA). The geographical overlap in co-infection is a common phenomenon. However, there is continued paucity of information on how the co-infection influence the blood glucose and insulin profiles in the infected host. Animal models are ideal to elucidate effects of co-infection on disease outcomes and hence, blood glucose, insulin and glycogen profiles were assessed in Sprague-Dawley rats co-infected with P. berghei ANKA (Pb) and Trichinella zimbabwensis (Tz), a tissue-dwelling nematode.

Methods

One-hundred-and-sixty-eight male Sprague-Dawley rats (weight range 90-150 g) were randomly divided into four separate experimental groups: Control (n = 42), Pb-infected (n = 42), Tz-infected (n = 42) and Pb- + Tz-infected group (n = 42). Measurement of Pb parasitaemia was done daily throughout the experimental study period for the Pb and the Pb + Tz group. Blood glucose was recorded every third day in all experimental groups throughout the experimental study period. Liver and skeletal muscle samples were harvested, snap frozen for determination of glycogen concentration.

Results

Results showed that Tz mono-infection and Tz + Pb co-infection did not have blood glucose lowering effect in the host as expected. This points to other possible mechanisms through which tissue-dwelling parasites up-regulate the glucose store without decreasing the blood glucose concentration as exhibited by the absence of hypoglycaemia in Tz + Pb co-infection group. Hypoinsulinemia and an increase in liver glycogen content was observed in Tz mono-infection and Tz + Pb co-infection groups of which the triggering mechanism remains unclear.

Conclusions

To get more insights into how glucose, insulin and glycogen profiles are affected during plasmodium-helminths co-infections, further studies are recommended where other tissue-dwelling helminths such as Taenia taeniformis which has strobilocercus as the metacestode in the liver to mimic infections such as hydatid disease in humans are used.

Trichinella-induced immunomodulation: Another tale of helminth success

Trichinella spiralis is a unique parasite in that both the adults and larvae survive in two different intracellular niches in the same host. The immune response, albeit intense, is highly modulated to ensure the survival of both the host and the parasite. It is skewed to T helper 2 and regulatory arms. Diverse cells from both the innate and adaptive compartments of immunity, including dendritic cells, T regulatory cells, and alternatively activated macrophages are thought to mediate such immunomodulation. The parasite has also an outstanding ability to evade the immune system by several elaborate processes. The molecules derived from the parasites including Trichinella, particularly the components of the excretory-secretory products, are being continually identified and explored for the potential of ameliorating the immunopathology in animal models of diverse inflammatory and autoimmune human diseases. Herein we discuss the various aspects of Trichinella-induced immunomodulation with a special reference to the practical implications of the immune system manipulation in alleviating or possibly curing human diseases.

Effects of co-administration of Ganoderma terpenoid extract with chloroquine on inflammatory markers and antioxidant status in Plasmodium berghei-infected mice

OBJECTIVE

To understand the protective effects of Ganoderma terpenoid extract (GTE) against Plasmodium berghei-malarial infection in mice, the present study was carried out to evaluate the effects of GTE in combination with chloroquine disulphate (CQ) on erythrocyte-selected inflammatory markers and antioxidant defense status in P. berghei-infected mice.

METHODS

P. berghei-infected mice were divided into six groups: infected control (IC) group, administered 1 mL Tween 20; GTE₁₀₀ and GTE₂₅₀ groups, administered 100 and 250 mg/kg GTE, respectively; GT₁₀₀ + CQ and GT₂₅₀ + CQ groups, co-administered 100 and 250 mg/kg GTE plus 30 mg/kg CQ, respectively; and CQ group, administered 30 mg/kg CQ. A separate group of non-infected mice were given 1 mL Tween 20, and served as a normal control group (NC). Extract and drug were dissolved in Tween 20 and administered orally once daily for 12 consecutive days. At the end of the treatment period, mice were anesthetized with chloroform and sacrificed by cervical dislocation. Plasma was prepared from blood obtained from each mouse. Parameters evaluated at the end of the treatment period include parasitemia, red blood cell count, hematocrit, malondialdehyde (MDA), glutathione (GSH), catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10).

RESULTS

Infected mice treated with a combination of GTE and CQ (GT₁₀₀ + CQ and GT₂₅₀ + CQ groups) showed significantly reduced parasitemia levels (P < 0.05) compared to those administered GTE alone as well as IC. Significant improvement in body weight (P < 0.05) was also observed in infected mice treated with a combination of GTE and CQ (GT₁₀₀ + CQ and GT₂₅₀ + CQ groups), compared to mice receiving GTE alone (GTE₁₀₀ and GTE₂₅₀ groups). Plasma MDA and TNF-α concentrations were significantly lowered, and IL-10 concentration was significantly increased in GT₁₀₀ + CQ and GT₂₅₀ + CQ groups, relative to the IC group (P < 0.05). GSH concentration and SOD, CAT and GPx activities were significantly higher in GT₁₀₀ + CQ and GT₂₅₀ + CQ groups compared to the GTE₁₀₀, GTE₂₅₀, IC and NC groups (P < 0.05).

CONCLUSION

Data generated in this study showed that GTE enhanced the anti-plasmodial action of CQ in mice through its anti-inflammatory and antioxidant activities.