Propolis derivatives inhibit the systemic inflammatory response and protect hepatic and neuronal cells in acute septic shock

Prophylactic use of standardized extract of propolis of Apis mellifera (EPP-AF®) reduces lung inflammation and improves survival in experimental lethal sepsis

ETHNOPHARMACOLOGICAL RELEVANCE

Sepsis poses one of the biggest public health problems, necessitating the search for new therapeutic alternatives. For centuries, propolis has been widely used in folk medicine to treat various inflammatory and infectious diseases. Given its extensive use, it has excellent potential as an adjuvant treatment for patients with sepsis.

OBJECTIVE

This study evaluated prophylactic treatment with standardized propolis extract (EPP-AF®) and followed the prognosis of sepsis induced by ligation and cecal ligation and puncture (CLP).

METHODS

Initially, for survival assessment, Swiss mice were separated into five groups: Sham (false operated), control (PBS), ATB (received antibiotic, 8 mg/kg), P10 (received EPP-AF®, 10 mg/kg), and P100 (received EPP-AF®, 100 mg/kg). The animals received PBS, antibiotic, or EPP-AF® by the subcutaneous route 6 h before the CLP procedure. Animal survival was assessed every 12 h for five days when all of them were euthanized.

RESULTS

We show that the treatment with EPP-AF® significantly increased the life expectancy of animals with sepsis compared to the control group. Interestingly, prophylactic treatment with EPP-AF® showed no effect on the number of colony-forming units in the peritoneum, blood, or lung. However, there was a decrease in cellular influx in the peritoneum. This alteration was unrelated to the number of bone marrow cells or the differential counting of peripheral blood cells. The coagulogram remained unchanged, including the number of platelets and prothrombin time-activated partial thromboplastin time. However, the inflammatory infiltrate and bleeding in the lung tissue were lower in the animals that received EPP-AF®.

CONCLUSION

Thus, it was possible to conclude that prophylactic treatment with EPP-AF® preserved the lung parenchyma, resulting in an increased lifespan of mice with sepsis. It can be a helpful adjuvant in prophylactic treatment with antibiotics in presurgical conditions.

Effects of short- and long-term use of propolis extracts on liver and kidney in rats

Propolis is widely used as a supplementary food product for its health benefits. The aim of this study was to determine the effects of commercial propolis extracts on the liver and kidney. Propolis extracts (250 mg/kgbw/day) were administered orally to adult male Wistar albino rats in solvents of ethanol, propylene glycol, water, and olive oil. Liver enzyme levels were determined biochemically in blood samples, and histopathological examinations were performed on the liver. Damage rate in both kidney tissue in the propolis-ethanol extract group increased significantly compared with the other groups after 30 and 90 days of application (p < .05). According to the results, ethanol, used as a common solvent in propolis products, may adversely affect the liver in long-term use. The data indicate that propolis-olive oil extract may be an essential alternative due to its effective and reliable properties.

Comparison of time to negative conversion of SARS-CoV-2 between young and elderly among asymptomatic and mild COVID-19 patients: a cohort study from a national containment center

Objective

We aimed to study the relationship between age and time to negative conversion of SARS-CoV-2 in patients with asymptomatic and mild forms of COVID-19.

Methods

We conducted a cohort study including all patients diagnosed with COVID-19 from the national COVID-19 containment center of Tunisia. Patients were subdivided into two cohorts: (under 60 years) and (over 60 years) and were followed up until PCR negativization. Log rank test and Cox regression were applied to compare time to negative conversion between the old group and the young group.

Results

The study included 289 patients with non-severe forms of COVID-19. Age over 60 was significantly associated with delayed negative conversion in male sex (Hazard ratio (HR): 1.9; 95% CI: 1.2-3.07) and among patients with morbid conditions (HR:1.68; 95% CI: 1.02-2.75) especially diabetics (HR: 2.06; 95% CI: 1.01-4.21). This association increased to (HR:2.3; 95% CI: 1.13-4.66) when male sex and comorbidities were concomitantly present and rose to (HR: 2.63; 95% CI: 1.02-6.80) for men with diabetes. Cox regression analysis revealed a significantly delayed negative conversion in symptomatic patients. Significant interaction was observed between gender and age and between age and chronic conditions.

Conclusion

Age is associated with delayed negative conversion of viral RNA in certain subgroups. Identifying these subgroups is crucial to know how prioritize preventive strategies in elderly.

Propolis efficacy on SARS-COV viruses: a review on antimicrobial activities and molecular simulations

This current study review provides a brief review of a natural bee product known as propolis and its relevance toward combating SARS-CoV viruses. Propolis has been utilized in medicinal products for centuries due to its excellent biological properties. These include anti-oxidant, immunomodulatory, anti-inflammatory, anti-viral, anti-fungal, and bactericidal activities. Furthermore, studies on molecular simulations show that flavonoids in propolis may reduce viral replication. While further research is needed to validate this theory, it has been observed that COVID-19 patients receiving propolis show earlier viral clearance, enhanced symptom recovery, quicker discharge from hospitals, and a reduced mortality rate relative to other patients. As a result, it appears that propolis could probably be useful in the treatment of SARS-CoV-2-infected patients. Therefore, this review sought to explore the natural properties of propolis and further evaluated past studies that investigated propolis as an alternative product for the treatment of COVID-19 symptoms. In addition, the review also highlights the possible mode of propolis action as well as molecular simulations of propolis compounds that may interact with the SARS-CoV-2 virus. The activity of propolis compounds in decreasing the impact of COVID-19-related comorbidities, the possible roles of such compounds as COVID-19 vaccine adjuvants, and the use of nutraceuticals in COVID-19 treatment, instead of pharmaceuticals, has also been discussed.

Effects of a Short-Term Lipopolysaccharides Challenge on Mouse Brain and Liver Peroxisomal Antioxidant and β-oxidative Functions: Protective Action of Argan Oil

During sepsis, the imbalance between oxidative insult and body antioxidant response causes the dysfunction of organs, including the brain and liver. Exposing mice to bacterial lipopolysaccharides (LPS) results in a similar pathophysiological outcome. The protection offered by argan oil was studied against LPS-induced oxidative stress, dysregulation of peroxisomal antioxidants, and β-oxidation activities in the brain and liver. In a short-term LPS treatment, lipid peroxidation (malonaldehyde assay) increased in the brain and liver with upregulations of proinflammatory tumor necrosis factor (Tnf)-α and anti-inflammatory interleukin (Il)-10 genes, especially in the liver. Although exposure to olive oil (OO), colza oil (CO), and argan oil (AO) prevented LPS-induced lipid peroxidation in the brain and liver, only AO exposure protected against liver inflammation. Remarkably, only exposure to AO prevented LPS-dependent glutathione (GSH) dysregulation in the brain and liver. Furthermore, exposure to AO increased more efficiently than OO and CO in both organs, peroxisomal antioxidant capacity via induction of catalase (Cat) gene, protein and activity expression levels, and superoxide dismutase (Sod1) mRNA and activity levels. Interestingly, LPS decreased protein levels of the peroxisomal fatty acid-ATP binding cassette (ABC) transporters, ABCD1 and ABCD2, and increased acyl-CoA oxidase 1 (ACOX1) protein expression. Moreover, these LPS effects were attenuated for ABCD1 and ACOX1 in the brain of mice pretreated with AO. Our data collectively highlight the protective effects of AO against early oxidative stress caused by LPS in the brain and liver and their reliance on the preservation of peroxisomal functions, including antioxidant and β-oxidation activities, making AO a promising candidate for the prevention and management of sepsis.

Role of inflammation and oxidative stress in tissue damage associated with cystic fibrosis: CAPE as a future therapeutic strategy

Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, responsible for the synthesis of the CFTR protein, a chloride channel. The gene has approximately 2000 known mutations and all of them affect in some degree the protein function, which makes the pathophysiological manifestations to be multisystemic, mainly affecting the respiratory, gastrointestinal, endocrine, and reproductive tracts. Currently, the treatment of the disease is restricted to controlling symptoms and, more recently, a group of drugs that act directly on the defective protein, known as CFTR modulators, was developed. However, their high cost and difficult access mean that their use is still very restricted. It is important to search for safe and low-cost alternative therapies for CF and, in this context, natural compounds and, mainly, caffeic acid phenethyl ester (CAPE) appear as promising strategies to assist in the treatment of the disease. CAPE is a compound derived from propolis extracts that has antioxidant and anti-inflammatory activities, covering important aspects of the pathophysiology of CF, which points to the possible benefit of its use in the disease treatment. To date, no studies have effectively tested CAPE for CF and, therefore, we intend with this review to elucidate the role of inflammation and oxidative stress for tissue damage seen in CF, associating them with CAPE actions and its pharmacologically active derivatives. In this way, we offer a theoretical basis for conducting preclinical and clinical studies relating the use of this molecule to CF.

Propolis increases Foxp3 expression and lymphocyte proliferation in HIV-infected people: A randomized, double blind, parallel-group and placebo-controlled study

HIV infection and the prolonged use of antiretroviral therapy (ART) contribute to persistent inflammation and immune deregulation in people living with HIV/AIDS (PLWHA). Propolis is a bee product with plenty of biological properties, including immunomodulatory and anti-inflammatory action. This work aimed to evaluate possible changes in the immune/inflammatory response in PLWHA under ART after propolis intake. Asymptomatic PLWHA were double-blindly randomized into parallel groups receiving propolis (500 mg/day, n = 20) for 3 months or placebo (n = 20). Plasma cytokines (TNF-α, IL-2, IL-4, IL-6, IL-10 and IL17) were evaluated by cytometric bead array; cytokine production by PBMC (IFN-γ, IL-5, IL-17, IL-10, IL-1β, IL-18, and IL-33) was assessed by ELISA; gene expression (T-bet, GATA-3, RORγt and Foxp3) was determined by RT-qPCR, and cell proliferation was analysed by flow cytometry using CFSE staining. The average of gender, age, CD4⁺/CD8⁺ T cell count, time of diagnosis and treatment were similar in both groups. No differences were observed in cytokine levels nor in inflammasome activation. However, Pearson's correlation showed that IL-10 was directly correlated to CD4⁺ T cell count and inversely to IFN-γ after treatment with propolis. Foxp3 expression and lymphocyte proliferation increased in the propolis group. Data suggested that daily propolis consumption may improve the immune response and decrease the inflammatory status in asymptomatic PLWHA under ART.

Protective Role of Mytilus edulis Hydrolysate in Lipopolysaccharide-Galactosamine Acute Liver Injury

Acute liver injury in its terminal phase trigger systemic inflammatory response syndrome with multiple organ failure. An uncontrolled inflammatory reaction is difficult to treat and contributes to high mortality. Therefore, to solve this problem a search for new therapeutic approaches remains urgent. This study aimed to explore the protective effects of M. edulis hydrolysate (N2-01) against Lipopolysaccharide-D-Galactosamine (LPS/D-GalN)-induced murine acute liver injure and the underlying mechanisms. N2-01 analysis, using Liquid Chromatography Mass Spectrometry (LCMS) metabolomic and proteomic platforms, confirmed composition, molecular-weight distribution, and high reproducibility between M. edulis hydrolysate manufactured batches. N2-01 efficiently protected mice against LPS/D-GalN-induced acute liver injury. The most prominent result (100% survival rate) was obtained by the constant subcutaneous administration of small doses of the drug. N2-01 decreased Vascular Cell Adhesion Molecule-1 (VCAM-1) expression from 4.648 ± 0.445 to 1.503 ± 0.091 Mean Fluorescence Intensity (MFI) and Interleukin-6 (IL-6) production in activated Human Umbilical Vein Endothelial Cells (HUVECs) from 7.473 ± 0.666 to 2.980 ± 0.130 ng/ml in vitro. The drug increased Nitric Oxide (NO) production by HUVECs from 27.203 ± 2.890 to 69.200 ± 4.716 MFI but significantly decreased inducible Nitric Oxide Synthase (iNOS) expression from 24.030 ± 2.776 to 15.300 ± 1.290 MFI and NO production by murine peritoneal lavage cells from 6.777 ± 0.373 µm to 2.175 ± 0.279 µm. The capability of the preparation to enhance the endothelium barrier function and to reduce vascular permeability was confirmed in Electrical Cell-substrate Impedance Sensor (ECIS) test in vitro and Miles assay in vivo. These results suggest N2-01 as a promising agent for treating a wide range of conditions associated with uncontrolled inflammation and endothelial dysfunction.

Green propolis extract attenuates acute kidney injury and lung injury in a rat model of sepsis

Sepsis is the leading cause of acute kidney injury (AKI) and lung injury worldwide. Despite therapeutic advances, sepsis continues to be associated with high mortality. Because Brazilian green propolis (GP) has promising anti-inflammatory, antioxidant, and immunomodulatory properties, we hypothesized that it would protect kidneys and lungs in rats induced to sepsis by cecal ligation and puncture (CLP). Male Wistar rats were divided into groups-control (sham-operated); CLP (CLP only); and CLP + GP (CLP and treatment with GP at 6 h thereafter)-all receiving volume expansion and antibiotic therapy at 6 h after the procedures. By 24 h after the procedures, treatment with GP improved survival, attenuated sepsis-induced AKI, and restored renal tubular function. Whole-blood levels of reduced glutathione were higher in the CLP + GP group. Sepsis upregulated the Toll-like receptor 4/nuclear factor-kappa B axis in lung and renal tissues, as well as increasing inflammatory cytokine levels and macrophage infiltration; all of those effects were attenuated by GP. Treatment with GP decreased the numbers of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling-positive cells in renal and lung tissue, as well as protecting the morphology of the renal mitochondria. Our data open the prospect for clinical trials of the use of GP in sepsis.

The Pluripotent Activities of Caffeic Acid Phenethyl Ester

Caffeic acid phenethyl ester (CAPE) is a strong antioxidant extracted from honey bee-hive propolis. The mentioned compound, a well-known NF-κB inhibitor, has been used in traditional medicine as a potent anti-inflammatory agent. CAPE has a broad spectrum of biological properties including anti-viral, anti-bacterial, anti-cancer, immunomodulatory, and wound-healing activities. This review characterizes published data about CAPE biological properties and potential therapeutic applications, that can be used in various diseases.

Clinical characteristics of hospitalized mild/moderate COVID-19 patients with a prolonged negative conversion time of SARS-CoV-2 nucleic acid detection

Background

The impact of COVID-19 has been devastating on a global scale. The negative conversion time (NCT) of SARS-CoV-2 RNA is closely related to clinical manifestation and disease progression in COVID-19 patients. Our study aimed to predict factors associated with prolonged NCT of SARS-CoV-2 RNA in mild/moderate COVID-19 patients.

Methods

The clinical features, laboratory data and treatment outcomes of COVID-19 patients were retrospectively analyzed. Then univariate and multivariate analysis were used to screen out risk factors of influencing prolonged NCT of SARS-CoV-2 RNA.

Results

Thirty-two hospitalized mild/moderate COVID-19 patients were enrolled. The general clinical symptoms were cough (78.1%), fever (75%), diarrhea (68.8%), expectoration (56.3%), and nausea (37.5%). More than 40% of the patients had decreased erythrocyte, hemoglobin and leucocyte and 93.8% patients were detected in abnormalities of chest CT. The median NCT of SARS-CoV-2 RNA was 19.5 days (IQR: 14.25–25). Univariate analysis found fever, nausea, diarrhea and abnormalities in chest CTs were positively associated with prolonged NCT of viral RNA (P< 0.05). The multivariate Cox proportional hazard model revealed that fever [Exp (B), 0.284; 95% CI, 0.114–0.707; P<0.05] and nausea [Exp (B), 0.257; 95%CI, 0.096–0.689; P<0.05] were two significant independent factors.

Conclusions

Fever and nausea were two significant independent factors in prolonged NCT of viral RNA in mild/moderate COVID-19 patients, which provided a useful references for disease progression and treatment of COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05851-z.

CAPE and Neuroprotection: A Review

Propolis, a product of the honey bee, has been used in traditional medicine for many years. A hydrophobic bioactive polyphenolic ester, caffeic acid phenethyl ester (CAPE), is one of the most extensively investigated active components of propolis. Several studies have indicated that CAPE has a broad spectrum of pharmacological activities as anti-oxidant, anti-inflammatory, anti-viral, anti-fungal, anti-proliferative, and anti-neoplastic properties. This review largely describes CAPE neuroprotective effects in many different conditions and summarizes its molecular mechanisms of action. CAPE was found to have a neuroprotective effect on different neurodegenerative disorders. At the basis of these effects, CAPE has the ability to protect neurons from several underlying causes of various human neurologic diseases, such as oxidative stress, apoptosis dysregulation, and brain inflammation. CAPE can also protect the nervous system from some diseases which negatively affect it, such as diabetes, septic shock, and hepatic encephalopathy, while numerous studies have demonstrated the neuroprotective effects of CAPE against adverse reactions induced by different neurotoxic substances. The potential role of CAPE in protecting the central nervous system (CNS) from secondary injury following various CNS ischemic conditions and CAPE anti-cancer activity in CNS is also reviewed. The structure–activity relationship of CAPE synthetic derivatives is discussed as well.

Propolis nanoparticles modulate the inflammatory and apoptotic pathways in carbon tetrachloride-induced liver fibrosis and nephropathy in rats

This study assessed the use of emulsion-produced propolis nanoparticles for treating carbon tetrachloride (CCl4 )-induced liver fibrosis and nephropathy on albino rat model. The evaluation of hepatotoxicity, nephrotoxicity, and the treatment outcomes involved biochemical investigations of blood samples as well as molecular analysis, and histopathological assessment for liver and kidney tissue samples. CCl4 treatment caused elevated biochemical indicators of hepatotoxic and nephrotoxic effects as detected by liver and kidney functions tests, which improved gradually with propolis nanoparticles treatment. The molecular studies showed an increase in transforming growth factor β (TGF-β), Nephrin, and Caspase-9, while Bcl-2 levels dropped in both liver and kidney tissue samples; such changes were normalized after treatment. The histological findings confirm both biochemical and molecular studies. Our results indicated that propolis nanoparticles had an anti-inflammatory effect as proved by decreased expression of TGF-β in liver tissue and Nephrin in kidney tissue. The propolis nanoparticles showed an anti-apoptotic effect on liver and kidney tissue increasing the expression of Bcl-2 and decreasing the expression of Caspase-9.

Propolis from southeastern Brazil produced by Apis mellifera affects innate immunity by modulating cell marker expression, cytokine production and intracellular pathways in human monocytes

OBJECTIVES

Propolis is a bee-made product used for centuries due to its diverse biological properties, including its immunomodulatory action. This work aimed at investigating whether propolis may affect monocyte functions challenged with retinoic acid (RA), B subunit of Escherichia coli heat-labile enterotoxin (EtxB), human melanoma-associated antigen-1 (MAGE-1) and lipopolysaccharide (LPS).

METHODS

Monocytes from healthy donors were treated with the stimuli separately or in the presence of propolis. Cell viability was evaluated by MTT assay, cell marker expression was assessed by flow cytometry, cytokine production by ELISA, gene expression by RT-qPCR.

KEY FINDINGS

Propolis alone maintained TLR-2, TLR-4, HLA-DR, CD40 and CD80 expression in the monocytes; however, its combination with either MAGE-1 or LPS decreased CD40 expression triggered by the stimuli. Propolis maintained RA action on cell marker expression. Propolis inhibited TNF-α (with either EtxB or MAGE-1) and IL-6 (with either RA or MAGE-1), and increased IL-10 (with MAGE-1) production. Propolis downmodulated LC3 expression induced by LPS. It also induced a lower NF-kB expression than control cells and its combination with RA induced a higher expression than the stimulus alone.

CONCLUSIONS

Propolis potentially affected innate immunity by downmodulating the monocytes pro-inflammatory activity.

Propolis: A useful agent on psychiatric and neurological disorders? A focus on CAPE and pinocembrin components

Propolis consists of a honeybee product, with a complex mix of substances that have been widely used in traditional medicine. Among several compounds present in propolis, caffeic acid phenethyl ester (CAPE), and pinocembrin emerge as two principal bioactive compounds, with benefits in a variety of body systems. In addition to its well-explored pharmacological properties, neuropharmacological activities have been poorly discussed. In an unprecedented way, the present review addresses the current finding on the promising therapeutic purposes of propolis, focusing on CAPE and pinocembrin, highlighting its use on neurological disturbance, as cerebral ischemia, neuroinflammation, convulsion, and cognitive impairment, as well as psychiatric disorders, such as anxiety and depression. In addition, we provide a critical analysis, discussion, and systematization of the molecular mechanisms which underlie these central nervous system effects. We hypothesize that the pleiotropic action of CAPE and pinocembrin, per se or associated with other substances present in propolis may result in the therapeutic activities reported. Inhibition of the pro-inflammatory cascade, antioxidant activity, and positive neurotrophic modulatory effects consist of the main molecular targets attributed to CAPE and pinocembrin in health benefits.

Antifibrotic effect of curcumin, N-acetyl cysteine and propolis extract against bisphenol A-induced hepatotoxicity in rats: Prophylaxis versus co-treatment

AIMS

Bisphenol A (BPA) has been shown to induce liver fibrosis in rodents. Therefore, this study examined the protective effect of a triple combination of curcumin (Cur), N-acetyl cysteine (NAC) and propolis (Prp) extract against BPA-induced hepatic fibrosis.

METHODS

100 Wistar male rats were equally assigned into 10 groups; one group was designated as control. 10 rats were gavaged with BPA (50 mg/kg/day) for 8 wk and left un-treated (BPA group). The remaining 80 rats were divided into 8 groups, distributed in 2 models. Protective model: rats were daily co-treated with BPA and Cur (100 mg/kg, p.o) or NAC (150 mg/kg, p.o) or Prp (200 mg/kg, p.o) or their combination for 8 wk. Preventive model: rats were daily treated with Cur or NAC or Prp or their combination for 4 wk before BPA administration and then in the same manner as protective model.

KEY FINDINGS

Current treatment interventions significantly alleviated BPA-induced hepatic damage and fibrosis. They also restored pro-oxidant/antioxidant balance, shifted cytokine balance towards the anti-inflammatory side, decreasing interleukin-1β/interleukin-10 ratio. Moreover, these compounds seem to exert anti-apoptotic effects by increasing the immunoexpression of B-cell lymphoma 2 in hepatocytes and decreasing hepatic caspase-3 content. Finally, they ameliorated extracellular matrix turn over through down-regulation of matrix metalloproteinase-9 and up-regulation of tissue inhibitor of matrix metalloproteinase-2 genetic expression.

SIGNIFICANCE

Current treatments guarded against BPA-induced hepatic fibrosis due to their antioxidant, anti-inflammatory and anti-apoptotic properties, decreasing extracellular matrix turnover. Interestingly, the triple therapy provided hepatoprotection superior to monotherapy. Besides, prophylactic and concurrent treatments seem to be more effective than concurrent treatments.

Risk factors for disease progression in COVID-19 patients

BACKGROUND

Coronavirus disease (COVID-19) is rapidly spreading worldwide. Although 10-20% of patients with COVID-19 have severe symptoms, little is known about the risk factors related to the aggravation of COVID-19 symptoms from asymptomatic or mild to severe disease states.

METHODS

This retrospective study included 211 patients who were asymptomatic or with mild presentations of COVID-19. We evaluated the differences in demographic and clinical data between the cured (discharged to home) and transferred (aggravated to severe-stage COVID-19) groups.

RESULTS

A multivariate logistic analysis showed that body temperature, chills, initial chest X-ray findings, and the presence of diabetes were significantly associated with predicting the progression to severe stage of COVID-19 (p < 0.05). The odds ratio of transfer in patients with COVID-19 increased by 12.7-fold for abnormal findings such as haziness or consolidation in initial chest X-ray, 6.32-fold for initial symptom of chills, and 64.1-fold for diabetes.

CONCLUSIONS

Even if patients are asymptomatic or have mild symptoms, clinicians should closely observe patients with COVID-19 presenting with chills, body temperature > 37.5 °C, findings of pneumonia in chest X-ray, or diabetes.

The potential neuroprotective role of mesenchymal stem cell-derived exosomes in cerebellar cortex lipopolysaccharide-induced neuroinflammation in rats: a histological and immunohistochemical study

Lipopolysaccharide (LPS) is an endotoxin that prompts neuroinflammation and initiates neurodegenerative disorders. Exosome is a recent therapeutic agent for many diseases such as neurological diseases. This study aimed to evaluate the potential protective role of bone marrow mesenchymal stem cell-derived exosomes (BMSC-EXs) in cerebellar cortex LPS-induced neuroinflammation in rats. Twenty-seven adult male rats were divided into three groups: Group I: control rats; Group II: LPS-treated rats; Group III: LPS/BMSC-EXs-treated rats. Cerebellar specimens were taken and processed for histological and immunohistochemical analysis. Morphometrical studies and statistical analysis were done. Groups II showed neuronal degeneration and apoptosis. The mean number of Purkinje cells was significantly (P<0.01)  decreased, while glial fibrillary acidic protein (GFAP) immunoexpression was significantly increased in the neuroglial cells. Ultrastructural examination showed shrunken Purkinje cells with irregular nuclei and disrupted mitochondria. Group III showed improvement of most of the changes mentioned previously. EXs therapy is a promising neuroprotective tool for treatment of LPS-induced neuroinflammation.

Radiation-Induced Heart Diseases: Protective Effects of Natural Products

Cardiovascular diseases (CVDs) account for the majority of deaths worldwide. Radiation-induced heart diseases (RIHD) is one of the side effects following exposure to ionizing radiation (IR). Exposure could be from various forms such as diagnostic imaging, radiotherapy for cancer treatment, as well as nuclear disasters and nuclear accidents. RIHD is mostly observed after radiotherapy for thoracic malignancies, especially left breast cancer. RIHD may affect the supply of blood to heart muscles, leading to an increase in the risk of heart attacks to irradiated persons. Due to its dose-limiting consequence, RIHD has a negative effect on the therapeutic efficacy of radiotherapy. Several methods have been proposed for protection against RIHD. In this paper, we review the use of natural products, which have shown promising results for protection against RIHD.

Connection between Systemic Inflammation and Neuroinflammation Underlies Neuroprotective Mechanism of Several Phytochemicals in Neurodegenerative Diseases

Oxidative damage, mitochondrial dysfunction, and neuroinflammation are strongly implicated in the pathogenesis of neurodegenerative diseases including Alzheimer's disease (AD) and Parkinson's disease (PD), and a substantial portion of elderly population at risk of these diseases requires nutritional intervention to benefit health due to lack of clinically relevant drugs. To this end, anti-inflammatory mechanisms of several phytochemicals such as curcumin, resveratrol, propolis, polyunsaturated fatty acids (PUFAs), and ginsenosides have been extensively studied. However, correlation of the phytochemicals with neuroinflammation or brain nutrition is not fully considered, especially in their therapeutic mechanism for neuronal damage or dysfunction. In this article, we review the advance in antioxidative and anti-inflammatory effects of phytochemicals and discuss the potential communication with brain microenvironment by improved gastrointestinal function, enhanced systemic immunity, and neuroprotective outcomes. These data show that phytochemicals may modulate and suppress neuroinflammation of the brain by several approaches: (1) reducing systemic inflammation and infiltration via the blood-brain barrier (BBB), (2) direct permeation into the brain parenchyma leading to neuroprotection, (3) enhancing integrity of disrupted BBB, and (4) vagal reflex-mediated nutrition and protection by gastrointestinal function signaling to the brain. Therefore, many phytochemicals have multiple potential neuroprotective approaches contributing to therapeutic benefit for pathogenesis of neurodegenerative diseases, and development of strategies for preventing these diseases represents a considerable public health concern and socioeconomic burden.

Hippocampus and cerebellum damage in sepsis induced by lipopolysaccharide in aged rats - Pregabalin can prevent damage

BACKGROUNDS

The aim of this study was to investigate the oxidative damage and inflammatory effects in the hippocampus and cerebellum in lipopolysaccharide (LPS)-induced sepsis model and possible ameliorating effects of pregabalin (PG).

METHODS

Twenty four female Wistar Albino rats (12 month old) were divided into 3 groups as follows: Group I (Control; 0.1 ml/gavage and i.p. saline, single dose), Group II (LPS; 5 mg/kg LPS, i.p, single dose), Group III (LPS + PG; 5 mg/kg LPS, i.p, single dose + 30 mg/kg, gavage, single dose). DNA damage, ischemia-modified albumin (IMA), total oxidant status (TOS), total antioxidant status (TAS) oxidative stress index (OSI), leukocyte (WBC), lymphocyte, neutrophil, hemoglobin (HGB), erythrocyte (RBC), and thrombocyte counts were measured in blood and brain tissues. Histopathological and immunohistochemical evaluation of Caspase- 3, G-CSF, IL-6, SAA, iNOS expressions were conducted using hippocampus and cerebellum tissues.

RESULTS

Comet analysis score, lymphocytes, neutrophils, WBC, IMA, TOS and OSI values were increased in Group II compared with to Group I (p < 0.05). IMA levels in blood, TOS and OSI levels in the brain were significantly decreased in Group III compared to Group II (p < 0.05). We observed increased hemorrhages, neutrophils, leukocytes infiltrations and neuron degeneration in Group II compared to Group I. Caspase 3, G-CSF, IL-6, SAA, iNOS expressions were increased in group II compared to Group I (p < 0.001).

CONCLUSION

Pregabalin partly ameliorated the damage caused by the exposure to LPS in hippocampus and cerebellum; however, further studies are needed to determine pregabalin's possible protective effects at different doses and with different techniques.

Anti-inflammatory effects of Chinese propolis in lipopolysaccharide-stimulated human umbilical vein endothelial cells by suppressing autophagy and MAPK/NF-κB signaling pathway

This study aimed to investigate the possible benefits of Chinese poplar propolis (CP) in inhibiting inflammation using vascular endothelial cells (VECs) cultured in a nutrient-rich condition exposed to lipopolysaccharide (LPS). Cell proliferation was detected by sulforhodamine B assay and EdU kit. The production of reactive oxygen species (ROS) and level of mitochondrial membrane potential were determined with fluorescent probe DCHF and JC-1, respectively. Protein expression was examined by immunofluorescence staining and western blotting. The results showed that CP (6.25, 12.5, and 25 μg/mL) significantly reduced LPS-induced cytotoxicity, and when challenged with CP substantially suppressed ROS overproduction and protected mitochondrial membrane potential. CP treatment significantly inhibited autophagy by inhibiting LC3B distribution and accumulation, and elevating the p62 level in an mTOR-independent manner but mainly by suppressing the translocation of p53 from the cytoplasm to the nucleus. Furthermore, CP treatment markedly reduced protein levels of TLR4 at 12 and 24 h and significantly suppressed nuclear translocation of NF-κB p65 from cytoplasm to nucleus. In addition, CP treatment significantly reduced the phosphorylation of JNK, ERK1/2, and p38 MAPK. Our findings demonstrated that CP protects VECs from LPS-induced oxidative stress and inflammation, which might be associated with depressing autophagy and MAPK/NF-κB signaling pathway. The results provided novel insights for the potential use of nutrient-rich propolis against inflammation.

Iraqi propolis increases degradation of IL-1β and NLRC4 by autophagy following Pseudomonas aeruginosa infection

Autophagy is a cellular process for maintaining cellular homeostasis. This process can be induced by different factors, such as immune stimuli and pathogen-associated molecules. Autophagy has an important role in the control of IL-1β secretion by macrophages and other cell types. In present study, we describe a novel role for Iraqi propolis affecting autophagy in controlling the secretion of IL-1β in bone-marrow macrophages (BMDMs). After infection with Pseudomonas aeruginosa in the presence of propolis, the degradation of IL-1β was induced, and the activity of inflammasome was reduced. Iraqi propolis-induced autophagy in in vitro and in vivo models decreased the levels of IL-1β and caspase-1. Results indicated that IL-1β pathway production is regulated by autophagy via two different novel mechanisms, namely, regulation of the activation of NLRC4 inflammasome and IL-1β targeting for lysosomal degradation.

Protective Effect of Propolis in Proteinuria, Crystaluria, Nephrotoxicity and Hepatotoxicity Induced by Ethylene Glycol Ingestion

BACKGROUND AND AIMS

Propolis is a natural honeybee product with wide biological activities and potential therapeutic properties. The aim of the study is to evaluate the protective effect of propolis extract on nephrotoxicity and hepatotoxicity induced by ethylene glycol in rats.

METHODS

Five groups of rats were used. Group 1 received drinking water, group 2 received 0.75% ethylene-glycol in drinking water, group 3 received 0.75% ethylene-glycol in drinking water along with cystone 500 mg/kg/body weight (bw) daily, group 4 received 0.75% ethylene-glycol in drinking water along with propolis extract at a dose of 100 mg/kg/bw daily, and group 5 received 0.75% ethylene-glycol in drinking water along with propolis extract at a dose of 250 mg/kg/bw daily. The treatment continued for a total of 30 d. Urinalyses for pH, crystals, protein, creatinine, uric acid and electrolytes, and renal and liver function tests were performed.

RESULTS

Ethylene-glycol increased urinary pH, urinary volume, and urinary calcium, phosphorus, uric acid and protein excretion. It decreased creatinine clearance and magnesium and caused crystaluria. Treatment with propolis extract or cystone normalized the level of magnesium, creatinine, sodium, potassium and chloride. Propolis is more potent than cystone. Propolis extract alleviates urinary protein excretion and ameliorates the deterioration of liver and kidney function caused by ethylene glycol.

CONCLUSIONS

Propolis extract has a potential protective effect against ethylene glycol induced hepatotoxicity and nephrotoxicity and has a potential to treat and prevent urinary calculus, crystaluria and proteinuria.

Anti-Inflammatory Properties of Brazilian Green Propolis Encapsulated in a γ-Cyclodextrin Complex in Mice Fed a Western-Type Diet

Ageing is often accompanied by chronic inflammation. A fat- and sugar-rich Western-type diet (WTD) may accelerate the ageing phenotype. Cell culture studies have indicated that artepillin C-containing Brazilian green propolis exhibits anti-inflammatory properties. However, little is known regarding its anti-inflammatory potential in mouse liver in vivo. In this study, female C57BL/6NRj wild-type mice were fed a WTD, a WTD supplemented with Brazilian green propolis supercritical extract (GPSE) encapsulated in γ-cyclodextrin (γCD) or a WTD plus γCD for 10 weeks. GPSE-γCD did not affect the food intake, body weight or body composition of the mice. However, mRNA levels of the tumour necrosis factor α were significantly downregulated (p < 0.05) in these mice compared to those in the WTD-fed controls. Furthermore, the gene expression levels of other pro-inflammatory markers, including serum amyloid P, were significantly (p < 0.001) decreased following GPSE-γCD treatment. GPSE-γCD significantly induced hepatic ferritin gene expression (p < 0.01), which may contribute to its anti-inflammatory properties. Conversely, GPSE-γCD did not affect the biomarkers of endogenous antioxidant defence, including catalase, glutathione peroxidase-4, paraoxonase-1, glutamate cysteine ligase and nuclear factor erythroid 2-related factor-2 (Nrf2). Overall, the present data suggest that dietary GPSE-γCD exhibits anti-inflammatory, but not antioxidant activity in mouse liver in vivo. Thus, GPSE-γCD has the potential to serve as a natural hepatoprotective bioactive compound for dietary-mediated strategies against chronic inflammation.

Caffeic Acid Cyclohexylamide Rescues Lethal Inflammation in Septic Mice through Inhibition of IκB Kinase in Innate Immune Process

Targeting myeloid differentiation protein 2 (MD-2) or Toll-like receptor 4 (TLR4) with small molecule inhibitor rescues the systemic inflammatory response syndrome (SIRS) in sepsis due to infection with Gram-negative bacteria but not other microbes. Herein, we provided IκB kinase β (IKKβ) in innate immune process as a molecular target of caffeic acid cyclohexylamide (CGA-JK3) in the treatment of polymicrobial TLR agonists-induced lethal inflammation. CGA-JK3 ameliorated E. coli lipopolysaccharide (LPS, MD-2/TLR4 agonist)-induced endotoxic shock, cecal ligation and puncture (CLP)-challenged septic shock or LPS plus D-galactosamine (GalN)-induced acute liver failure (ALF) in C57BL/6J mice. As a molecular basis, CGA-JK3 inhibited IKKβ-catalyzed kinase activity in a competitive mechanism with respect to ATP, displaced fluorescent ATP probe from the complex with IKKβ, and docked at the ATP-binding active site on the crystal structure of human IKKβ. Furthermore, CGA-JK3 inhibited IKKβ-catalyzed IκB phosphorylation, which is an axis leading to IκB degradation in the activating pathway of nuclear factor-κB (NF-κB), in macrophages stimulated with TLR (1/2, 2/6, 4, 5, 7, 9) agonists from Gram-positive/negative bacteria and viruses. CGA-JK3 consequently interrupted IKKβ-inducible NF-κB activation and NF-κB-regulated expression of TNF-α, IL-1α or HMGB-1 gene, thereby improving TLRs-associated redundant inflammatory responses in endotoxemia, polymicrobial sepsis and ALF.

Hesperidin prevents lipopolysaccharide-induced endotoxicity in rats

CONTEXT

Lipopolysaccharide (LPS) is a major trigger of septic shock resulting in multiple organ damage through excessive stimulation of the host's immune cells resulting in the release of cytokines. Previous studies have shown that hesperidin has several beneficial properties against inflammation and oxidative stress.

OBJECTIVE

The influence of hesperidin on endotoxemia, endothelial dysfunction, inflammation, and oxidative stress was investigated using a murine model of sepsis.

MATERIALS AND METHODS

Rats were pretreated for 15 d with three doses (50 mg/kg, 100 mg/kg, and 200 mg/kg) of hesperidin prior to LPS administration. Afterwards, the levels of biomarkers of endotoxemia, endothelial dysfunction, and oxidative stress were assessed. Reverse transcriptase PCR technique was used to assess the expression of hepatic proinflammatory cytokines.

RESULTS

Hesperidin pretreatment significantly (p < 0.05) reduced circulating endotoxin, as well as the levels of bactericidal permeability increasing protein and procalcitonin, and the associated endothelial dysfunction by reducing the levels of plasma soluble intercellular adhesion molecules 1 and inducible nitric oxide (iNO) synthase. There was also down-regulation of the expression of gene for interleukin 1α, interleukin 1β, interleukin 1 receptor, interleukin 6, and tumor necrosis factor α (TNFα) in the liver of rats treated with LPS as a result of hesperidin pretreatment. Hesperidin also showed anti-oxidative properties through the significant (p < 0.05) reduction of NO, hydroperoxides, and thiobarbituric acid reactive substances and increase of glutathione, glutathione reductase, glutathione peroxidase, and glutathione-S-transferase in the organs.

CONCLUSION

Different doses of hesperidin can prevent endotoxemia-induced oxidative stress as well as inflammatory and endothelial perturbation in rats when administered for as few as 15 d before exposure to endotoxin.

Propolis attenuates doxorubicin-induced testicular toxicity in rats

Doxorubicin (Dox), an effective anticancer agent, can impair testicular function leading to infertility. The present study aimed to explore the protective effect of propolis extract on Dox-induced testicular injury. Rats were divided into four groups (n=10). Group I (normal control), group II received propolis extract (200 mg kg(-1); p.o.), for 3 weeks. Group III received 18 mg kg(-1) total cumulative dose of Dox i.p. Group IV received Dox and propolis extract. Serum and testicular samples were collected 48 h after the last treatment. In addition, the effects of propolis extract and Dox on the growth of solid Ehrlich carcinoma in mice were investigated. Dox reduced sperm count, markers of testicular function, steroidogenesis and gene expression of testicular 3β-hydroxysteroid dehydrogenase (3β-HSD), 17β-hydroxysteroid dehydrogenase (17β-HSD) and steroidogenic acute regulatory protein (StAR). In addition, it increased testicular oxidative stress, inflammatory and apoptotic markers. Morphometric and histopathologic studies supported the biochemical findings. Treatment with propolis extract prevented Dox-induced changes without reducing its antitumor activity. Besides, administration of propolis extract to normal rats increased serum testosterone level coupled by increased activities and gene expression of 3ß-HSD and 17ß-HSD. Propolis extract may protect the testis from Dox-induced toxicity without reducing its anticancer potential.

Exogenous normal lymph reduces liver injury induced by lipopolysaccharides in rats

The liver is one of the target organs damaged by septic shock, wherein the spread of endotoxins begins. This study aimed to investigate the effects of exogenous normal lymph (ENL) on lipopolysaccharide (LPS)-induced liver injury in rats. Male Wistar rats were randomly divided into sham, LPS, and LPS+ENL groups. LPS (15 mg/kg) was administered intravenously via the left jugular vein to the LPS and LPS+ENL groups. At 15 min after the LPS injection, saline or ENL without cell components (5 mL/kg) was administered to the LPS and LPS+ENL groups, respectively, at a rate of 0.5 mL/min. Hepatocellular injury indices and hepatic histomorphology, as well as levels of P-selectin, intercellular adhesion molecule 1 (ICAM-1), myeloperoxidase (MPO), and Na⁺-K⁺-ATPase, were assessed in hepatic tissues. Liver tissue damage occurred after LPS injection. All levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in plasma as well as the wet/dry weight ratio of hepatic tissue in plasma increased. Similarly, P-selectin, ICAM-1, and MPO levels in hepatic tissues were elevated, whereas Na⁺-K⁺-ATPase activity in hepatocytes decreased. ENL treatment lessened hepatic tissue damage and decreased levels of AST, ALT, ICAM-1, and MPO. Meanwhile, the treatment increased the activity of Na⁺-K⁺-ATPase. These results indicated that ENL could alleviate LPS-induced liver injury, thereby suggesting an alternative therapeutic strategy for the treatment of liver injury accompanied by severe infection or sepsis.

Caffeic acid phenethyl ester, a promising component of propolis with a plethora of biological activities: a review on its anti-inflammatory, neuroprotective, hepatoprotective, and cardioprotective effects

Caffeic acid phenethyl ester (CAPE) is an important active component of honey bee propolis that possesses a plethora of biological activities. Propolis is used safely in traditional medicine as a dietary supplement for its therapeutic benefits. This review highlights the recently published data about CAPE bioavailability, anti-inflammatory, neuroprotective; hepatoprotective and cardioprotective activities. CAPE showed promising efficacy both in vitro and in vivo studies in animal models with minimum adverse effects. Its effectiveness was demonstrated in multiple target organs. Despite this fact, it has not been yet investigated as a protective agent or a potential therapy in humans. Investigation of CAPE efficacy in clinical trials is strongly encouraged to elucidate its therapeutic benefit for different human diseases after performing full preclinical toxicological studies and gaining more insights into its pharmacokinetics.

Protective effects of propolis on female rats' histopathological, biochemical and genotoxic changes during LPS induced endotoxemia

In recent years, propolis has been the object of extensive research for its antibacterial, antioxidant, anti-inflammatory, and antitumoral activities. This study aims to determine the hepatoprotective efficiency of propolis on experimental endotoxemia in rats. In the current study, fifty adult Sprague Dawley rats (weighing 200-300 g) were randomly divided into five groups of ten rats each. Normal saline solution was administered to the rats in the control group, while in the second group LPS (30 mg/kg), in the third group propolis (250 mg/kg), in the fourth group first propolis and then LPS (30 mg/kg), and in the fifth group, first LPS (30 mg/kg) and then propolis were given. Six hours after the application, biochemical (MDA levels) and histopathological changes as well as global DNA methylation analysis in the liver tissue samples were determined, while in the blood tissue samples Genomic Template Stability (GTS, %) was evaluated using RAPD-PCR profiles. The results demonstrated that the administration of propolis could have a protective effect against changes of both genomic stability values and methylation profiles, and it minimized the increase in MDA and tissue damage caused by LPS. In conclusion, the application of propolis prior to LPS-induced endotoxemia has shown to reduce hepatic damage.

The Inhibition of Inflammasome by Brazilian Propolis (EPP-AF)

Propolis extracts have gained the attention of consumers and researchers due to their unique chemical compositions and functional properties such as its anti-inflammatory activity. Recently, it was described a complex that is also important in inflammatory processes, named inflammasome. The inflammasomes are a large molecular platform formed in the cell cytosol in response to stress signals, toxins, and microbial infections. Once activated, the inflammasome induces caspase-1, which in turn induces the processing of inflammatory cytokines such as IL-1β and IL-18. So, to understand inflammasomes regulation becomes crucial to treat several disorders including autoinflammatory diseases. Since green propolis extracts are able to regulate inflammatory pathways, this work purpose was to investigate if this extract could also act on inflammasomes regulation. First, the extract was characterized and it demonstrated the presence of important compounds, especially Artepillin C. This extract was effective in reducing the IL-1β secretion in mouse macrophages and this reduction was correlated with a decrease in activation of the protease caspase-1. Furthermore, we found that the extract at a concentration of 30 μg/mL was not toxic to the cells even after a 18-hour treatment. Altogether, these data indicate that Brazilian green propolis (EPP-AF) extract has a role in regulating the inflammasomes.

Ethanolic extract of propolis, chrysin, CAPE inhibit human astroglia cells

PURPOSE

The aim of the present study was to examine the effect of freeze dried ethanolic extract of propolis (EEP), chrysin and caffeic acid phenethyl ester (CAPE) dependently on their concentrations on the viability and morphology of human astroglia cells line (SVGp12).

MATERIAL AND METHODS

Using gas chromatography - mass spectroscopy (GC-MS) we have established the composition of lyophilisate of EEP collected in Podlasie region (Poland). After 24 h, 48 h and 72 h of exposition to EEP or its ingredients we evaluated the survivability of human astroglia cells (SVGp12) using MTT test. Morphological analysis of human astroglia cells was defined by transmission electron microscope.

RESULTS

About 70 ingredients of EEP were evaluated by GC-MS. We obtained the strong decline of viability of astroglia cells SVGp12 approximately to 16% after EEP; 33% after chrysin and 25% after CAPE application. Condensed form of mitochondria observed in transmission electron microscope may indicate activation of intrinsic pathway of apoptosis induced by EEP, chrysin and CAPE in SVGp12 cell line.

CONCLUSION

This study showed that EEP, chrysin and CAPE reduced viability of human astroglia cells probably due to apoptosis process.