Structural Characterization and Bioactivity of a Titanium(IV)-Oxo Complex Stabilized by Mandelate Ligands

Research on titanium-oxo complexes (TOCs) is usually focused on their structure and photocatalytic properties. Findings from these investigations further sparked our interest in exploring their potential biological activities. In this study, we focused on the synthesis and structure of a compound with the general formula [Ti8O2(OiPr)20(man)4] (1), which was isolated from the reaction mixture of titanium(IV) isopropoxide with mandelic acid (Hman) in a molar ratio of 4:1. The structure (1) was determined using single-crystal X-ray diffraction, while spectroscopic studies provided insights into its physicochemical properties. To assess the potential practical applications of (1), its microcrystals were incorporated into a polymethyl methacrylate (PMMA) matrix, yielding composite materials of the type PMMA + (1) (2 wt.%, 5 wt.%, 10 wt.%, and 20 wt.%). The next stage of our research involved the evaluation of the antimicrobial activity of the obtained materials. The investigations performed demonstrated the antimicrobial activity of pure (1) and its composites (PMMA + (1)) against both Gram-positive and Gram-negative strains. Furthermore, MTT tests conducted on the L929 murine fibroblast cell line confirmed the lack of cytotoxicity of these composites. Our study identified (1) as a promising antimicrobial agent, which is also may be use for producing composite coatings.

Fever-Range Hyperthermia Promotes Macrophage Polarization towards Regulatory Phenotype M2b

Fever-range hyperthermia (FRH) is utilized in chronic disease treatment and serves as a model for fever's thermal component investigation. Macrophages, highly susceptible to heat, play a pivotal role in various functions determined by their polarization state. However, it is not well recognized whether this process can be modulated by FRH. To address this, we used two different macrophage cell lines that were treated with FRH. Next, to define macrophage phenotype, we examined their functional surface markers CD80 and CD163, intracellular markers such as inducible nitric oxide synthase (iNOS), arginase-1 (Arg-1), and the expression of interleukin-10 (IL-10) and tumor necrosis factor α (TNF-α). Additionally, in FRH-treated cells, we analyzed an expression of Toll-like receptor 4 (TLR-4) and its role in macrophage polarization. We also checked whether FRH can switch the polarization of macrophages in pro-inflammatory condition triggered by lipopolysaccharide (LPS). FRH induced M2-like polarization, evident in increased CD163, IL-10, and Arg-1 expression. Notably, elevated COX-2, TNF-α, and TLR-4 indicated potential pro-inflammatory properties, suggesting polarization towards the M2b phenotype. Additionally, FRH shifted lipopolysaccharide (LPS)-induced M1 polarization to an M2-like phenotype, reducing antimicrobial molecules (ROS and NO). In summary, FRH emerged as a modulator favoring M2-like macrophage polarization, even under pro-inflammatory conditions, showcasing its potential therapeutic relevance.

Endotoxin Tolerance Creates Favourable Conditions for Cancer Development

Endotoxin tolerance (ET) is an adaptive phenomenon of the immune system that protects the host from clinical complications due to repeated exposure of the body to endotoxins such as lipopolysaccharide (LPS). Since ET is an immunosuppressive mechanism in which a significant reprogramming of macrophages is observed, we hypothesized that it could influence cancer development by modifying the tumour environment. This study aimed to explore whether ET influences cancer progression by altering the tumour microenvironment. Endotoxin-tolerant macrophages (MoET) were examined for their impact on breast and colon cancer cells via direct interaction and conditioned media exposure. We characterized cancer cell behaviour by viability, clonogenic potential, motility, scratch assays, and 3D spheroidal assays. MoET-derived factors increased cancer cell viability, motility, and clonogenicity, suggesting a conducive environment for cancer development. Remarkably, despite reduced TNFα and IL-6 levels, MoET exhibited M1 polarization. These findings uncover an ET-associated macrophage reprogramming that fosters a favourable context for cancer progression across diverse tumours. Targeting ET could emerge as a promising avenue for cancer therapy and prevention.

Are Selected Cytokines and Epstein-Barr Virus DNA Load Predictors of Hepatological Complications of Epstein-Barr Virus Infection in Children?

The aim of the study was to evaluate tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), soluble intracellular adhesion molecules 1 (s-ICAM-1) and Epstein-Barr virus (EBV) DNA load levels as predictors of hepatological complications of EBV infection in children. The study group consisted of 54 children aged one to eighteen years, who were hospitalised from 1 December 2018 to 31 December 2020 in the Department of Paediatrics, Infectious Diseases and Hepatology and who had hepatological complications in the course of serologically and molecularly confirmed EBV infection. It was shown that IL-6, TNF-α, and s-ICAM-1 concentrations were the highest in patients with hepatitis and biliary pole damage. Higher EBV DNA viremia positively correlated with increased C-reactive protein (CRP) and TNF-α levels and increased leukocyte, lymphocyte, and monocyte counts. Increases in lymphocyte counts and TNF-α concentrations were observed along with increases in gamma-glutamyl transpeptidase (GGTP) activity. Increased concentrations of IL-6, TNF-α, and s-ICAM-1 may indicate the risk of hepatitis with concomitant biliary pole damage during EBV infection.

COVID-19 and Cancer Diseases-The Potential of Coriolus versicolor Mushroom to Combat Global Health Challenges

Coriolus versicolor (CV) is a common species from the Polyporaceae family that has been used in traditional Chinese herbal medicine for over 2000 years. Among well-described and most active compounds identified in CV are polysaccharopeptides, such as polysaccharide peptide (PSP) and Polysaccharide-K (PSK, krestin), which, in some countries, are already used as an adjuvant agent in cancer therapy. In this paper, research advances in the field of anti-cancer and anti-viral action of CV are analyzed. The results of data obtained in in vitro and in vivo studies using animal models as well as in clinical research trials have been discussed. The present update provides a brief overview regarding the immunomodulatory effects of CV. A particular focus has been given to the mechanisms of direct effects of CV on cancer cells and angiogenesis. A potential use of CV compounds in anti-viral treatment, including therapy against COVID-19 disease, has also been analyzed based on the most recent literature. Additionally, the significance of fever in viral infection and cancer has been debated, providing evidence that CV affects this phenomenon.

Fever-range whole body hyperthermia leads to changes in immune-related genes and miRNA machinery in Wistar rats

OBJECTIVE

Fever is defined as a rise in body temperature upon disease. Fever-range hyperthermia (FRH) is a simplified model of fever and a well-established medical procedure. Despite its beneficial effects, the molecular changes induced by FRH remain poorly characterized. The aim of this study was to investigate the influence of FRH on regulatory molecules such as cytokines and miRNAs involved in inflammatory processes.

METHODS

We developed a novel, fast rat model of infrared-induced FRH. The body temperature of animals was monitored using biotelemetry. FRH was induced by the infrared lamp and heating pad. White blood cell counts were monitored using Auto Hematology Analyzer. In peripheral blood mononuclear cells, spleen and liver expression of immune-related genes (IL-10, MIF and G-CSF, IFN-γ) and miRNA machinery (DICER1, TARBP2) was analyzed with RT-qPCR. Furthermore, RT-qPCR was used to explore miRNA-155 levels in the plasma of rats.

RESULTS

We observed a decrease in the total number of leukocytes due to lower number of lymphocytes, and an increase in the number of granulocytes. Furthermore, we observed elevated expressions of DICER1, TARBP2 and granulocyte colony-stimulating factor (G-CSF) in the spleen, liver and PBMCs immediately following FRH. FRH treatment also had anti-inflammatory effects, evidenced by the downregulation of pro-inflammatory macrophage migration inhibitor factor (MIF) and miR-155, and the increased expression of anti-inflammatory IL-10.

CONCLUSION

FRH affects the expression of molecules involved in inflammatory processes leading to alleviated inflammation. We suppose these effects may be miRNAs-dependent and FRH can be involved in therapies where anti-inflammatory action is needed.

Dual Effect of the Extract from the Fungus Coriolus versicolor on Lipopolysaccharide-Induced Cytokine Production in RAW 264.7 Macrophages Depending on the Lipopolysaccharide Concentration

Purpose

Extract from the fungus Coriolus versicolor (CV) is classified as an immunological response modifier. Previously, we have shown that this extract induces interleukin 6 (IL-6)-related extension of lipopolysaccharide (LPS)-induced fever. This study investigated the effect of CV extract on the production of pro-inflammatory cytokines and the expression of components of signal transduction pathways leading to the secretion of cytokines from RAW 264.7 macrophages stimulated with different doses of LPS.

Methods

RAW 264.7 cells were stimulated with CV extract alone or co-treated with CV extract and LPS. The level of IL-6 and tumour necrosis factor α (TNF-α) in the culture media was measured using ELISA. Protein expression of Toll-like receptor (TLR) 4, phosphorylated IκB (p-IκB), CD14 glycoprotein and phospho-phosphatidylinositol 3-kinase (p-PI3K) was evaluated using Western blot. The effects of TLR4, nuclear factor κB (NF-κB) and p-PI3K on cytokine secretion were estimated using inhibitors: TAK-242, JSH-23 and LY294002.

Results

CV extract itself stimulates the secretion of IL-6 and TNF-α and increases the expression of TLR4, p-IκB and p-PI3K. The presence of CV extract during the treatment of cells with lower concentrations of LPS (10 and 100 ng/mL) increases the cytokine production. Co-stimulation of cells with CV extract and LPS at a higher dose (500 ng/mL) decreases the secretion of cytokines. This effect is related to the changes in the expression of TLR4, CD14 glycoprotein, p-IκB and p-PI3K.

Conclusion

This is the first report showing that the CV extract-induced production of cytokines is mediated by the PI3K signalling pathway. This extract acts antagonistically or additively with LPS on the production of IL-6 and TNF-α, depending on the LPS concentration. Our results are helpful for illustrating the mechanisms for the immunostimulatory effect of CV extract in inflammatory processes.

Sawhorse-type ruthenium complexes with triazolopyrimidine ligands - what do they represent in terms of cytotoxic and CORM compounds?

Three sawhorse-type ruthenium(I) complexes containing purine analogs such as triazolopyrimidines of the general formula [Ru₂(CO)₄(μ-OOCCH₃)₂(L)₂], where L is 1,2,4-triazolo[1,5-a]pyrimidine (tp for 1), 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp for 2) and 5,7-diphenyl-1,2,4-triazolo[1,5-a]pyrimidine (dptp for 3), have been synthesized and characterized by elemental analysis, infrared analysis, multinuclear magnetic resonance spectroscopic techniques (¹H, ¹³C, ¹⁵N), and single-crystal X-ray diffraction (for 1 and 2). By assay with myoglobin, the photo-activated CO-releasing molecule (PhotoCORM) character of (1-3) has been confirmed, thus indicating the possibility of use in CO-based therapies. The importance of UV-induced modification has been investigated in the context of anticancer properties. Complexes (1) and (2) have been thoroughly screened for their in vitro cytotoxicity against various cancer cell lines: MCF-7 (breast cancer), HeLa (cervical cancer) and C32 (melanoma), as well as L929 normal fibroblasts in the dark and presence of UV-A light (365 nm). The results were compared with those for cisplatin and two reference ruthenium complexes, namely NAMI-A and KP1019. The most hydrophilic [Ru₂(CO)₄(μ-OOCCH₃)₂(tp)₂] (1) (log P = -1.12) was found to be more cytotoxic than (2), despite the lower cellular uptake measured by ICP-MS toward HeLa cells. Importantly, photo-induced stimulation of cells with (1) resulted in a lower decrease in the viability of L929 normal cells (IC₅₀ = 154.7 ± 6.5 μM) in comparison with HeLa cancer cells (IC₅₀ = 66.7 ± 3.4 μM). The photo-induced stimulation of (1) and (2) increases ROS generation, and their anticancer activity may be a partially ROS-dependent phenomenon.

Pigmentation Levels Affect Melanoma Responses to Coriolus versicolor Extract and Play a Crucial Role in Melanoma-Mononuclear Cell Crosstalk

Melanoma, the malignancy originating from pigment-producing melanocytes, is the most aggressive form of skin cancer and has a poor prognosis once the disease starts to metastasize. The process of melanin synthesis generates an immunosuppressive and mutagenic environment, and can increase melanoma cell resistance to different treatment modalities, including chemo-, radio- or photodynamic therapy. Recently, we have shown that the presence of melanin pigment inhibits the melanoma cell response to bioactive components of Coriolus versicolor (CV) Chinese fungus. Herein, using the same human melanoma cell line in which the level of pigmentation can be controlled by the L-tyrosine concentration in culture medium, we tested the effect of suppression of melanogenesis on the melanoma cell response to CV extract and investigated the cell death pathway induced by fungus extract in sensitized melanoma cells. Our data showed that susceptibility to CV-induced melanoma cell death is significantly increased after cell depigmentation. To the best of our knowledge, we are the first to demonstrate that CV extract can induce RIPK1/RIPK3/MLKL-mediated necroptosis in depigmented melanoma cells. Moreover, using the co-culture system, we showed that inhibition of the tyrosinase activity in melanoma cells modulates cytokine expression in co-cultured mononuclear cells, indicating that depigmentation of melanoma cells may activate immune cells and thereby influence a host anticancer response.

Protein-Bound Polysaccharides from Coriolus Versicolor Induce RIPK1/RIPK3/MLKL-Mediated Necroptosis in ER-Positive Breast Cancer and Amelanotic Melanoma Cells

BACKGROUND/AIMS

The induction of necroptosis, a form of caspase-independent cell death, represents one of the most promising anticancer therapeutic modalities, as necroptosis serves as an alternative way to eliminate apoptosis-resistant tumor cells. Here, we investigated whether protein-bound polysaccharides (PBPs) derived from the fungus Coriolus versicolor (CV) induce the necroptotic death pathway in breast cancer and melanoma cells.

METHODS

MCF-7 and SKMel-188 cells were exposed to PBPs either alone or in combination with necrostatin-1 (Nec-1), GSK'872 or necrosulfonamide (NSA), pharmacological inhibitors of the kinases receptor-interacting protein 1 kinase (RIPK1), receptor interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL), respectively, which are involved in necroptotic processes. The effects of cellular treatment with these inhibitors were quantified by measuring cell viability and reactive oxygen species (ROS) generation via 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and 2',7'-dichlorofluorescein diacetate (DCF-DA) assays, respectively. The morphological changes induced in these cells were detected using holotomographic (HT) microscopy. Activation of the TNF-α/TNFR1 pathway in the PBP-stimulated cells was evaluated using TNF-α-neutralizing antibody, qRT-PCR and immunofluorescence-based assays.

RESULTS

PBPs showed effective antitumor activity against MCF-7 and SKMel-188 cells. Cotreatment of the cells with Nec-1, GSK'872 or NSA abrogated PBP-induced cell death, and the cells were protected against membrane rupture. Moreover, breast cancer cell death caused by PBPs was mediated by induced activation of the TNF-α/TNFR1 pathway. Interestingly, the melanoma cells did not express TNF-α or TNFR1 after PBP stimulation; instead, PBPs triggered intracellular ROS generation, which was partially diminished by the inhibitors Nec-1, GSK'872 and NSA.

CONCLUSION

These results suggest that PBPs from the fungus CV induce RIPK1/RIPK3/MLKL-mediated necroptosis in breast cancer and melanoma cells, providing novel insights into the molecular effects of PBPs on cancer cells.

Protein-Bound Polysaccharides from Coriolus Versicolor Fungus Disrupt the Crosstalk Between Breast Cancer Cells and Macrophages through Inhibition of Angiogenic Cytokines Production and Shifting Tumour-Associated Macrophages from the M2 to M1 Subtype

BACKGROUND/AIMS

The tumour microenvironment is rich in multiple cells that influence cancer development. Among them, macrophages are the most abundant immune cells, which secrete factors involved in carcinogenesis. Since protein-bound polysaccharides (PBP) from the Coriolus versicolor fungus are believed to inhibit the growth of cancers, in the present study, we investigated whether these PBP influence crosstalk between triple-negative 4T1 breast cancer cells and RAW 264.7 macrophages.

METHODS

4T1 cells were cultured in conditioned media (CM) collected after: stimulation of the macrophages with PBP (CM-PBP) or incubation of non-treated macrophages (CM-NT). A co-cultured model of both cell lines was also employed to investigate the crosstalk between the cells. Cell viability was measured using the MTT assay. The levels of cytokines and chemokines were determined by ELISA methods. Commercial assay kits were used to assess the activity of both arginase 1 and inducible nitric oxide synthase (iNOS) and the level of cell migration.

RESULTS

The results revealed that CM-NT promotes proliferation and migration of 4T1 cells, and increases the secretion of pro-angiogenic factors (VEGF, MCP-1) by cancer cells. In contrast, CM-PBP inhibits 4T1 cell growth and migration, decreases the secretion of pro-angiogenic factors (VEGF, MCP-1) and upregulates the production of pro-inflammatory mediators (IL-6, TNF-α) with certain anti-tumoral properties Moreover, PBP-treated CM significantly decreases the level of M2 macrophage markers (arginase 1 activity, IL-10 and TGF-β concentrations), but upregulates iNOS activity and IL-6 and TNF-α production, which are M1 cell markers.

CONCLUSION

The results suggest that PBP suppress the favourable tumour microenvironment by inhibiting the crosstalk between 4T1 cells and macrophages through the regulation of production of angiogenic and inflammatory mediators, and modulating the M1/M2 macrophage subtype.

Let fever do its job: The meaning of fever in the pandemic era

Although fever is one of the main presenting symptoms of COVID-19 infection, little public attention has been given to fever as an evolved defense. Fever, the regulated increase in the body temperature, is part of the evolved systemic reaction to infection known as the acute phase response. The heat of fever augments the performance of immune cells, induces stress on pathogens and infected cells directly, and combines with other stressors to provide a nonspecific immune defense. Observational trials in humans suggest a survival benefit from fever, and randomized trials published before COVID-19 do not support fever reduction in patients with infection. Like public health measures that seem burdensome and excessive, fevers involve costly trade-offs but they can prevent infection from getting out of control. For infections with novel SARS-CoV-2, the precautionary principle applies: unless evidence suggests otherwise, we advise that fever should be allowed to run its course. Lay summary: For COVID-19, many public health organizations have advised treating fever with medicines such as acetaminophen or ibuprofen. Even though this is a common practice, lowering body temperature has not improved survival in laboratory animals or in patients with infections. Blocking fever can be harmful because fever, along with other sickness symptoms, evolved as a defense against infection. Fever works by causing more damage to pathogens and infected cells than it does to healthy cells in the body. During pandemic COVID-19, the benefits of allowing fever to occur probably outweigh its harms, for individuals and for the public at large.

New Insights into the Role of Glutathione in the Mechanism of Fever

Glutathione is one of the most important and potent antioxidants. The development of pharmacological compounds that can either increase or decrease glutathione concentrations has allowed investigation into the role of glutathione in various biological processes, including immune responses. Recent findings have shown that glutathione not only affects certain factors involved in immunological processes but also modifies complex immune reactions such as fever. Until recently, it was not known why some patients do not develop fever during infection. Data suggest that fever induction is associated with oxidative stress; therefore, antioxidants such as glutathione can reduce pyrexia. Surprisingly, new studies have shown that low glutathione levels can also inhibit fever. In this review, we focus on recent advances in this area, with an emphasis on the role of glutathione in immune responses accompanied by fever. We describe evidence showing that disturbed glutathione homeostasis may be responsible for the lack of fever during infections. We also discuss the biological significance of the antipyretic effects produced by pharmacological glutathione modulators.

Unbalanced thermoregulation in experimental autoimmune encephalitis induced in Lewis rats

Thermoregulation in patients suffering from multiple sclerosis (MS) is impaired and may result in either increases or decreases in body temperature. We have found that rat experimental autoimmune encephalitis (EAE), being a model of MS, is associated with body temperature disturbances as well. The purpose of the current study was to examine whether the altered body temperature in EAE-induced rats is due to either a deficit in thermoregulation or a controlled change in its set point. Subcutaneous injection of encephalitogenic emulsion into both pads of hind feet of the Lewis rats provoked EAE symptoms. Body temperature (Tb) of 6 rats was measured using biotelemetry system, and ambient temperature (Ta) preferred by 6 rats of another group was analyzed using thermal gradient system. Symptoms of EAE started 11 days postinjection and progressed quickly, culminating in a complete paralysis in rats placed in the gradient, which was associated with behavioural fever (accordingly, selected Ta raised to as much as 32.8 ± 0.5 °C vs 27.2 ± 0.6 °C in control rats). On the other hand, EAE rats, placed at a constant Ta of 24 °C, were able to generate fever (Tb of 37.8 ± 0.1 °C) at the start of the illness and then paralysis compromised fever (most likely due to an impairment of thermogenesis), which, surprisingly, resulted in recovery. We conclude that EAE onset in rats is associated with fever and its behavioural supporting leads to aggravation of the autoimmune neurotoxicity.

High mobility group box 1 protein released in the course of aseptic necrosis of tissues sensitizes rats to pyrogenic effects of lipopolysaccharide

It is still an open question as to whether or not aseptic injuries affect the generation of fever due to exogenous pyrogens including bacterial products. Therefore, in the present paper we have investigated the course of endotoxin fever in rats induced with lipopolysaccharide (LPS; given intraperitoneally in a dose of 50 μg/kg) 48 h after subcutaneous administration of turpentine oil (TRP; 0.1 mL per rat) that causes aseptic necrosis of tissues. We found that febrile response was significantly augmented in the animals pre-treated with turpentine compared to control rats (pre-treated with saline), and that observed excessive elevation of body temperature (Tb) was accompanied by enhanced release of fever mediators: interleukin-6 (IL-6) and prostaglandin E₂ (PGE₂) into plasma. Moreover, we found that sensitization to pyrogenic effects of lipopolysaccharide was associated with the increase in plasma level of high mobility group box 1 protein (HMGB1), one of the best-known damage-associated molecular patterns (DAMP), which was recently discovered as inflammatory mediator. Since the injection of anti-HMGB1 antibodies weakened observed hyperpyrexia in the animals pre-treated with turpentine, we conclude that HMGB1 is a plasma-derived factor released in the course of aseptic injury that enhances pyrogenic effects of LPS.

Extract from Coriolus versicolor fungus partially prevents endotoxin tolerance development by maintaining febrile response and increasing IL-6 generation

Endotoxin tolerance is defined as a reduced endotoxin-induced fever following repeated injections of lipopolysaccharide (LPS). Clinical examples of endotoxin tolerance include sepsis or cystic fibrosis. This state is characterized by inhibition of pro-inflammatory cytokines production and decrease in nuclear factor-kappa B (NF-κB) activation. Extract from Coriolus versicolor (CV) fungus is classified as a biological response modifier, which exhibits various biological activities, including immunopotentiating properties. The aim of study was to examine the effect of CV extract injection on body core temperature of Wistar rats during LPS-induced endotoxin tolerance. Body temperature was measured using biotelemetry. CV extract was injected intraperitoneally (100 mg kg^-1) 2 h prior to the first LPS peritoneal administration (50 μg/kg). Endotoxin tolerance was induced by three consecutive daily injections of LPS at the same dose. We also investigated the influence of CV extract pre-injection on the properties of peripheral blood mononuclear cells (PBMCs) isolated from LPS-treated rats in response to LPS stimulation ex vivo. PBMCs were isolated 2 h after the first LPS injection. After 24 h pre-incubation, the cells were stimulated with LPS (1 μg ml^-1) for 4 h. Our results revealed that CV extract partially prevents endotoxin tolerance through maintaining febrile response in rats following consecutive exposure to LPS. This state was accompanied by the ability of PBMCs isolated from rats injected with CV extract and LPS to release larger amounts of interleukin 6 and greater NF-κB activation in response to LPS stimulation ex vivo compared with the cells derived from rats injected only with LPS. Data also showed that CV extract augmented mitogenic effect of LPS on PBMCs and caused increase in reactive oxygen species generation. We concluded that CV extract, by a modifying effect on body temperature during endotoxin tolerance, can be consider as the immunostimulating agent, which prevents the non-specific refractoriness described in patients with sepsis or ischemia.

Buthionine sulfoximine, a glutathione depletor, attenuates endotoxic fever and reduces IL-1β and IL-6 level in rats

PURPOSE

The aim of our study was to investigate the effect of buthionine sulfoximine (BSO) - a glutathione depletor - on a course of endotoxic fever and IL-1β and IL-6 production.

MATERIAL AND METHODS

Male Wistar rats were subjected to intraperitoneal injection of lipopolysaccharide (LPS) from E. coli (50μg/kg, ip) to provoke fever. The level of spleen glutathione, plasma interleukin (IL)-1β, IL-6, and deep body temperature (Tb) were measured.

RESULTS

The LPS administration provoked fever (the average Tb was 38.14±0.05°C in NaCl/LPS-treated rats vs 37.10±0.03°C in control, not-treated rats; p<0.001). We observed that LPS injection induced a decrease in spleen glutathione level (7.67±0.92nM/g vs 13.27±0.47nM/g in not-treated rats; p<0.001). Furthermore, the injection of LPS provoked an elevation of plasma IL-1β and IL-6 concentration (from values below the lowest detectable standard in not-treated animals to 199.99±34.89pg/mL and 7500±542.21pg/mL, respectively; p<0.001). Pretreatment with BSO enhanced glutathione decrease in LPS-treated rats (5.05±0.49nM/g), and significantly affected fever (maximal Tb was 37.81±0.07°C in BSO/LPS-treated rats vs 38.76±0.11°C in NaCl/LPS-treated rats). BSO 4h after LPS injection decreased IL-1β and IL-6 gene expression (about 1.5 fold, and 2 fold, respectively). In a consequence we observed a decrease in plasma IL-6 concentration (4h after LPS injection plasma IL-6 was 4167.17±956.54pg/mL in BSO/LPS-treated rats vs 7500±542.21pg/mL in NaCl/LPS-treated rats; p<0.001), and later IL-1β (7h after LPS injection the IL-1β concentration was not detected).

CONCLUSION

Based on these data, we conclude that BSO, in addition to well-known application as an inhibitor of glutathione synthesis, is an antipyretic agent which reduces both IL-1β and IL-6 concentration.

N-Acetyl-l-cysteine exacerbates generation of IL-10 in cells stimulated with endotoxin in vitro and produces antipyresis via IL-10 dependent pathway in vivo

N-Acetyl-l-cysteine (NAC) is a well-known medication, primarily used as a mucolytic agent in pulmonary disease. Recently, we have found that NAC possesses antipyretic properties. The aim of the present study was to investigate the mechanism by which NAC attenuates fever. The concentration of interleukin (IL)-10 and prostaglandin (PG) E2 were measured using ELISA kit in the supernatants aspirated after stimulation of peripheral blood mononuclear cells (PBMCs) with lipopolysaccharide (LPS, 1μg/mL) and NAC (10mM). The body temperature of the Wistar rats was measured using biotelemetry system. To inhibit endotoxic fever, NAC (200mg/kg; i.p.) was injected into the rats one hour prior to the LPS administration (50μg/kg; i.p.). The pre-treatment of LPS-stimulated PBMCs with NAC resulted in a significant decrease in PGE2 concentration in comparison to the cells treated with LPS alone (PGE2 level was 386.1±61.9pg/mL vs. 2078.9±157.9pg/mL, respectively, p<0.001). Furthermore, in these cells we observed a significant increase in IL-10 level (142.1±2.62pg/mL in NAC+LPS stimulated cells vs. 54.4±0.6pg/mL in LPS stimulated cells, p<0.001). The injection of anti-IL-10 antibody into the rats abolished antipyretic properties of NAC. Body temperature in animals treated with anti-IL-10+NAC/LPS was 38.28±0.12°C vs. 37.73±0.06°C in IgG+NAC/LPS rats (p<0.001) and 38.31±0.20°C in NaCl/LPS-treated animals (n.s.). Based on these data, we conclude that NAC acts as an antipyretic via IL-10 stimulation. This finding provides a new insight into the immunopharmacology of NAC, and we believe that in a future it will contribute to the new and/or more accurate application of NAC in medicine.

LPS alters pattern of sickness behavior but does not affect glutathione level in aged male rats

Behavioral symptoms of sickness, such as fever and motor activity are a coordinated set of changes that develop during infection. The aim of study was to compare the sickness behaviour (SB) in healthy old and young rats treated with pyrogenic dose of endotoxin and to check their glutathione level. Before experimentation male Wistar rats were selected according to standard body mass, motor activity, and white blood cells count. Intraperitoneal injection of lipopolysaccharide (LPS) from E. coli was used to provoke SB. The level of liver glutathione, interleukin (IL) -6, deep body temperature (Tb) and motor activity were measured. Glutathione level in old and young rats did not differ significantly. In both young and old rats LPS administration provoked fever (the mean value of Tb was 38.06 ± 0.01 °C in old rats, and 38.19 ± 0.06 °C in young rats). LPS injection affected night-time activity in both groups (12 h averages were 1.56 ± 0.40 counts in old LPS-treated rats vs 2.74 ± 0.53 counts in not-treated old rats and 3.44 ± 0.60 counts for young LPS-treated vs 4.28 ± 0.57 counts for young not-treated rats). The injection of LPS provoked an elevation of plasma IL-6 concentration (from values below the lowest detectable standard in not-treated groups of animals to 6322.82 ± 537.00 pg/mL in old LPS-treated rats and 7415.62 ± 451.88 pg/mL in young LPS-treated rats). Based on these data, we conclude that good health of aged rats prevents decrease in the glutathione level. Old rats are still able to develop SB in response to pyrogenic dose of LPS, although its components have changed pattern compared to young animals.

Axonal regeneration inhibitors: emerging therapeutic options

For the most part, the central nervous system is unable to regenerate. The majority of injuries of vascular, inflammatory, degenerative and traumatic aetiology lead to an irreversible loss of central nervous system function. The paper presents the role of Nogo-A, MAG and OMgp proteins in the inhibition of central nervous system regeneration, and their potential clinical significance.

Analysis of the involvement of cytokines in allergy and breast cancer association

AIM OF THE STUDY

The existence of a correlation between allergy disorders and cancer diseases has been confirmed by several epidemiological studies. Although the molecular mechanism involved in this phenomenon remains unknown, there are data indicating that certain cytokines, engaged in allergic processes, have antineoplastic activities. The aim of the present study was to explore the association between advanced breast cancer and allergic state on the molecular level.

MATERIAL AND METHODS

We determined and compared the mRNA and protein expression of interleukin-1β (IL-1β), IL-4, IL-6, and interferon-γ (IFN-γ), cytokines known for antitumor properties, in the blood of advanced breast cancer patients and individuals with allergic diseases related to type 2 response. In addition, we performed an in vitro assay of reactivity of peripheral blood mononuclear cells after exogenous antigen stimulation. As a preliminary to molecular analysis we conducted a questionnaire study concerning the incidence of allergy among breast cancer patients and healthy subjects without malignancy.

RESULTS

The results of the survey study revealed a negative relation between breast cancer and allergy prevalence. Subsequent molecular analysis, however, did not show statistically significant differences in cytokines mRNA and protein expression levels between allergic patients and those with malignancy. The in vitro reactivity test also did not reveal marked differences between IL-1β, IL-4 and IL-6 production after PBMC triggering with exogenous antigen.

CONCLUSIONS

We concluded that the studied cytokines (IL-1β, IL-4, IL-6, and IFN-γ) are not engaged in breast cancer-allergy negative relation.

[Immunostimulatory properties of mistletoe extracts and their application in oncology]

For a long time cancer immunotherapy was overshadowed by chemotherapy and radiotherapy. Recently, "Science", one of the world's top scientific journals, named the stimulation of the body's own immune system to fight cancer cells as the "breakthrough of the year". In Germany, Switzerland and Austria, extracts derived from mistletoe (Viscum album L.) such as Iscador, Abnobaviscum, Helixor, Iscar, Iscucin and Isorel have been used in oncology for many years. These extracts have immunomodulating and immunostimulating properties, as demonstrated by experimental studies as well as in clinical trials. The aim of our paper is to present immunological disorders associated with cancer, which can be counteracted by treatment with extracts derived from mistletoe. Although these drugs cannot replace conventional cancer treatment, they may improve the patient's quality and length of life.

Polysaccharide peptide induces a tumor necrosis factor-α-dependent drop of body temperature in rats

Polysaccharide peptide (PSP) extracted from the Coriolus versicolor mushroom is frequently suggested as an adjunct to the chemo- or radiotherapy in cancer patients. It improves quality of the patients' life by decreasing pain, fatigue, loss of appetite, nausea, and vomiting. However, the effect of PSP on body temperature has not thus far been studied, although it is well known that treatment with other polysaccharide adjuvants, such as lipopolysaccharides, may induce fever. The aim of the present study, therefore, was to investigate the influence of PSP on temperature regulation in rats. We report that intraperitoneal injection of PSP provoked a dose-dependent decrease of temperature in male Wistar rats equipped with biotelemetry devices to monitor deep body temperature (Tb). The response was rapid (i.e., with latency of 15-20min), transient (lasting up to 5h post-injection), and accompanied by a significant elevation of the blood tumor necrosis factor-α (TNF-α) level. Pretreatment of the rats with anti-TNF-α antibody prevented the PSP-induced drop in Tb. Based on these data, we conclude that rats may develop an anapyrexia-like response to the injection of peptidopolysaccharide rather than fever, and the response was TNF-α-dependent.

Thermal and motor behavior in experimental autoimmune encephalitis in Lewis rats

Thermoregulation in patients, who suffer from multiple sclerosis (MS) is impaired and may result in either increases or decreases in body temperature. Disturbances in body temperature correlate with acute relapses, and for this reason, it is an important issue in everyday life of those who suffer from MS. Although rat experimental autoimmune encephalitis (EAE) appeared useful for the examination of current therapies against MS, it has not been thoroughly investigated in terms of body temperature. The purpose of this study was to examine the effect of EAE induction on thermal and motor behavior in the rats. Subcutaneous injection of encephalitogenic emulsion into both pads of hind feet of the Lewis rats provoked symptoms of EAE. Body temperature (T(b)) and motor activity of rats were measured using biotelemetry system. We report a significant increase in body temperature within 24 h prior to the EAE manifestation (12 h average of T(b) for EAE induced animals was higher by 1.07 ± 0.06 °C during day-time and by 0.5 ± 0.05 °C during night time in comparison to the control rats). On the other hand, the onset of EAE symptoms was associated with gradual decrease of body temperature, and during the first night-time T(b) was lower by 1.03 ± 0.08 °C in comparison to the control rats. The inhibition of the motor activity started from the night time, 2 days before EAE onset. On the basis of our data, we concluded that the pattern of body temperature changes after EAE induction may be considered as useful symptom (prodrom) to predict precisely the time of EAE onset. Furthermore, we suggest that EAE in rats may be a suitable model to study mechanism of body temperature alternations observed in MS patients.

Antipyretic activity of N-acetylcysteine

N-acetylcysteine (NAC) has been used primarily as a mucolytic agent for the treatment of respiratory diseases. It has been recently suggested that NAC also possesses some anti-inflammatory properties. The aim of the present study is to investigate the effects of NAC on fever provoked either by bacterial lipopolysaccharide (LPS) or a turpentine-induced aseptic abscess in the rats. The body temperature (Tb) and the motor activity of the Wistar rats were measured using biotelemetry system. NAC (200 mg/kg) was injected intraperitoneally (i.p.) One hour prior to the injection of LPS (50 μg/kg; i.p.) or turpentine (100 μl/rat; subcutaneously) into separate groups of rats. The injection of NAC into normal non-febrile rats did not alter the animal circadian rhythm in Tb and activity. Pretreatment of rats with NAC resulted in the reduction of both infectious and aseptic fevers. Fever in rats was associated with inhibition of the motor activity and loss of body weight. Treatment with NAC diminished the decrease of motor activity and had no effect on the reduction of body weight in rats injected with LPS. It did, however, attenuate the drop of body mass in rats challenged with turpentine oil. Based on these data one may conclude that NAC, in addition to its mucolytic, antioxidant and anti-inflammatory properties, may be considered as a therapeutic fever-modulating agent under certain clinical circumstances.

Hypoxia-induced sickness behaviour

Sickness behaviour (SB) consists of the set of adaptive responses of the host to severe infections and inflammation. It includes, among others, the thermoregulatory responses such as regulated increase (fever) and/or decrease (anapyrexia) of body temperature (T(b)), decrease of motor activity (lethargy), and loss of appetite (hypophagia) resulting in a transient loss of body weight. It is thought that SB is partially induced by the immune-derived mediators such as cytokines and prostaglandins acting on the central nervous system. It has repeatedly been shown, on the other hand, that severe infections (pneumonia, tissue septicemia) can impair processes of the gases exchange both in the lungs and in distal tissues including brain, which may lead to hypoxia of the affected organs. Therefore, we have tested the hypothesis that hypoxia may also provoke SB. The study was conducted on freely moving biotelemetered mice kept at 28 degrees C ambient and 12/12 h light/dark cycle. We demonstrate that mice exposed for 7 days to hypoxia (11%O(2)) displayed all symptoms of SB. Interleukin-6 deficient mice (IL-6 KO) revealed reduced SB symptoms under hypoxic conditions. Recovery of the hypoxia-exposed mice to a normal rhythm in T(b), motor activity and feeding was unaffected by mepacrine, a phospholipase A(2) blocker. The recovery, however, was significantly impaired by indomethacin, a cyclooxygenase inhibitor. Exposure to hypoxemia resulted in significant elevation of plasma IL-6 in both untreated and treated with lipopolysaccharide (LPS) mice. It inhibited, however, a generation of blood prostaglandins (PGE(2)) in mice. Based on these data we conclude that IL-6 and accumulation of free arachidonic acid in biomembranes contribute to hypoxemia- induced SB.

Role of prostaglandins in heme-induced fever

Brain stroke is often accompanied by a high fever, which is insensitive to a blockade with classic antipyretic drugs known to inhibit the synthesis of prostaglandin E(2) (PGE(2)), a proximal mediator of fever associated with infection. The molecular mechanism of fever associated with stroke is mostly unknown, and has not been thoroughly investigated. One characteristics of the stroke is an extravasation of the erythrocytes into the brain tissue followed by a release of hemoglobin and free heme. In the present study we have tested the hypothesis that free heme itself can induce fever after releasing into the brain. The study was conducted on Sprague Dawley rats instrumented with biotelemetry devices to monitor deep body temperature, and implanted with brain cannulae projected to the lateral ventricle. We demonstrate that heme-L-lysinate microinfused intraventricularly (icv) induces a dose-dependent fever lasting ca. 8 hours. Injection of heme-L-lysinate provoked a significant elevation of PGE(2) in the rat cerebro-spinal fluid collected 3 hours post-injection. The fever induced by heme-L-lysinate was blocked by an icv injection of anti- PGE(2) antibody. It was not affected, however, by intraperitoneal administration of indomethacin, a cyclooxygenase inhibitor. We conclude that heme-induced fever may underlie the stroke fever.

Pyrogenicity of CpG-DNA in mice: role of interleukin-6, cyclooxygenases, and nuclear factor-κB

Bacterial DNA containing unmethylated cytosine-phosphate-guanosine motif (CpG-DNA) has been identified as a pathogen-associated molecular pattern, which is recognized by Toll-like receptors and activates immune cells to produce cytokines. The aim of the study was to characterize the ability of CpG-DNA to induce fever in mice. Intravenous administration of unmethylated CpG-DNA 1826 triggered an elevation of body temperature (Tb) lasting several hours. The magnitude of Tbelevation increased with an increase of dose of the oligonucleotide (administered in a range from 0.01 mg/kg to 1.0 mg/kg). A fever-like increase of Tbin mice was partially dependent on IL-6, as IL-6 deficient mice responded with reduced fever to the CpG-DNA 1826. Meloxicam and sulindac sulfide, inhibitors of cyclooxygenases, reduced fever in mice challenged with CpG-DNA 1826, indicating that the process may also depend on prostaglandins. In fact, plasma levels of prostaglandin E2, as well as IL-6, increased at 4 h postinjection of CpG-DNA 1826 into mice. These data demonstrate that the pathophysiological mechanism of the increase of Tbinduced by CpG-DNA 1826 is similar to fever induced by LPS. Both LPS and CpG-DNA 1826 failed to produce elevation of Tbin mice deficient for a nuclear factor-κB (NF-κB) gene, further supporting the hypothesis that the two pyrogens provoke fever, using the same components of the cellular signaling metabolism. However, parthenolide, an inhibitor of I-κB kinase reduced fever due to CpG-DNA 1826, and did not affect fever to LPS, suggesting that the two structurally dissimilar pyrogens may affect different intracellular pathways leading to the upregulation of NF-κB. In support of this hypothesis, we demonstrate that C3H/HeJ mice, known to exhibit a mutation in the Toll-like receptor-4 gene, do not respond with fever to LPS. They respond, however, with fever after injection of CpG-DNA 1826. We conclude that bacterial DNA shares with components of the bacterial wall the capacity to elicit fever and may, consequently, be part of a novel class of exogenous pyrogens.