Exploring the potency of polyphenol-rich blend from Lonicera caerulea var. Kamtschatica sevast., Aronia melanocarpa, and Echinacea purpurea: Promising anti-inflammatory, antioxidant, and antiviral properties.

Previous studies have highlighted the beneficial properties of plants rich in polyphenols, such as Lonicera caerulea var. Kamtschatica Sevast. (LCK), Aronia melanocarpa (AM), and Echinacea purpurea (EP). These plants have demonstrated antioxidant, immunomodulatory, and potential antiviral effects. Thus, the objective of this study was to investigate the impact of the ELA blend, a polyphenol-rich blend containing EP, LCK, and AM, on the cellular mechanisms involved in viral infection. To assess the effects of the ELA blend, various experiments were conducted using A549 cells and a mucociliary tissue 3D model called EpiAirway™. Inflammation and oxidative stress induced by LPS were evaluated through measurements of SOD activity, ELISA, and qPCR analysis. Additionally, antiviral assays were performed in a cell-present environment to examine the blend's effectiveness against HCoV-OC43. The results showed that the ELA blend-treated group exhibited reduced expression of IL1B, CXCL8, ICAM1, MCP1, and RELA in both A549 cells and EpiAirway™. Moreover, the blend enhanced the expression of CAT, HMOX1, SOD1, and SOD2 in A549 cells. The antiviral activity of the ELA blend was also investigated, i.e. its influence on viral replication cycle, to determine the potential as an antiviral preparation. At the highest non-cytotoxic concentration, the ELA blend demonstrated a 87.5 % reduction in viral titer when administered simultaneously with HCoV-OC43. It emphasize potential ability of the preparation to block viral entry to the host cells. At the same time, ELA blend did not express virucidal activity, i.e. inactivation of free viral particles, against HCoV-OC43. In conclusion, ELA blend displayed antiviral activity and exhibited immunomodulatory and antioxidant effects. Based on these findings, it can be concluded that ELA blend has potential for the prevention and treatment of viral infections.

Endocytosis and Alzheimer's disease.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and is the most common cause of dementia. The pathogenesis of AD still remains unclear, including two main hypotheses: amyloid cascade and tau hyperphosphorylation. The hallmark neuropathological changes of AD are extracellular deposits of amyloid-ß (Aß) plaques and intracellular neurofibrillary tangles (NFTs). Endocytosis plays an important role in a number of cellular processes including communication with the extracellular environment, nutrient uptake, and signaling by the cell surface receptors. Based on the results of genetic and biochemical studies, there is a link between neuronal endosomal function and AD pathology. Taking this into account, we can state that in the results of previous research, endolysosomal abnormality is an important cause of neuronal lesions in the brain. Endocytosis is a central pathway involved in the regulation of the degradation of amyloidogenic components. The results of the studies suggest that a correlation between alteration in the endocytosis process and associated protein expression progresses AD. In this article, we discuss the current knowledge about endosomal abnormalities in AD.

Artificial light and neurodegeneration: does light pollution impact the development of Alzheimer's disease?

Two multidimensional problems of recent times - Alzheimer's disease and light pollution - seem to be more interrelated than previously expected. A series of studies in years explore the pathogenesis and the course of Alzheimer's disease, yet the mechanisms underlying this pathology remain not fully discovered and understood. Artificial lights which accompany civilization on a daily basis appear to have more detrimental effects on both environment and human health than previously anticipated. Circadian rhythm is affected by inappropriate lighting conditions in particular. The consequences are dysregulation of the sleep-wake cycle, gene expression, neuronal restructuring, brain's electricity, blood flow, metabolites' turnover, and gut microbiota as well. All these phenomena may contribute to neurodegeneration and consequently Alzheimer's disease. There is an increasing number of research underlining the complexity of the correlation between light pollution and Alzheimer's disease; however, additional studies to enhance the key tenets are required for a better understanding of this relationship.

Cognitive Decline in Early and Premature Menopause.

Early and premature menopause, or premature ovarian insufficiency (POI), affects 1% of women under the age of 40 years. This paper reviews the main aspects of early and premature menopause and their impact on cognitive decline. Based on the literature, cognitive complaints are more common near menopause: a phase marked by a decrease in hormone levels, especially estrogen. A premature reduction in estrogen puts women at a higher risk for cardiovascular disease, parkinsonism, depression, osteoporosis, hypertension, weight gain, midlife diabetes, as well as cognitive disorders and dementia, such as Alzheimer's disease (AD). Experimental and epidemiological studies suggest that female sex hormones have long-lasting neuroprotective and anti-aging properties. Estrogens seem to prevent cognitive disorders arising from a cholinergic deficit in women and female animals in middle age premature menopause that affects the central nervous system (CNS) directly and indirectly, both transiently and in the long term, leads to cognitive impairment or even dementia, mainly due to the decrease in estrogen levels and comorbidity with cardiovascular risk factors, autoimmune diseases, and aging. Menopausal hormone therapy from menopause to the age of 60 years may provide a "window of opportunity" to reduce the risk of mild cognitive impairment (MCI) and AD in later life. Women with earlier menopause should be taken care of by various specialists such as gynecologists, endocrinologists, neurologists, and psychiatrists in order to maintain their mental health at the highest possible level.

Sex Differences in Innate Immune Response of Peripheral Blood Leukocytes of Alzheimer's Disease Patients.

Neurodegenerative disorders, including Alzheimer's disease (AD), are associated with a disruption of normal immune function that could potentially impact the brain. In AD sex and gender have been noted as relevant to disease prevalence or clinical manifestation. It is suggested that disease progression could vary as a result of the different inflammation state among males and females. The objective was to investigate sex-dependent difference in innate immunity of AD patients and healthy, age-matched controls. The level of innate immunity was measured with test based on peripheral blood leukocytes (PBLs) resistance to viral infection (vesicular stomatitis virus, VSV) ex vivo. Cytokine: TNF-α, IFN-γ, IL-1ß, IL-10 production by uninfected and VSV-infected PBLs ex vivo with enzyme-linked immunosorbent assay were examined. In contrast to controls, women with AD exhibit lower average level of innate immunity than AD men. The mean level of TNF-α, IL-10 and IL-1ß was higher in AD men than in AD women whereas such changes were not observed among controls. The level of IFN-γ was higher in AD than in controls. PBLs from AD did not increase IFN-γ production after viral infection in contrast to controls. Leukocytes from women with AD exhibited a weaker response to viral infection and much less cytokine production compared to men with AD. It is important to consider sex as a biological variable in AD as it shows promises to advance our understanding of mechanisms of AD pathology and may be the basis for future treatment of AD.

Ginkgo Biloba Leaf Extract Improves an Innate Immune Response of Peripheral Blood Leukocytes of Alzheimer's Disease Patients.

BACKGROUND: One of the main features of Alzheimer's disease (AD) pathology is failure in innate immune response and chronic inflammation. Lack of effective AD treatment means that more attention is paid to alternative therapy and drugs of natural origin, such as extract of Ginkgo biloba (EGb). The purpose of this study was to investigate the effect of EGb on the mechanisms of innate immune response of peripheral blood leukocytes (PBLs) in AD patients. METHODS: In AD patients and healthy-age matched controls, the effect of EGb on two of innate immune reactions, i.e., PBLs resistance to viral infection ex vivo and production of cytokines, namely TNF-α, IFN-γ, IL-1ß, IL-10, IL-15, and IFN-α, were investigated. The influence of EGb on inflammatory-associated genes expression that regulate innate immune response to viral infection and cytokine production, namely IRF-3, IRF-7, tetherin, SOCS1, SOCS3, NFKB1, p65, and MxA was also examined. RESULTS: A beneficial effect of EGb especially in AD women was observed. EGb decreased production of TNF-α, IFN-γ, and IL-10 and increased IL-15 and IL-1ß. The effect was more pronouncement in AD group. EGb also downregulated expression of investigated genes. CONCLUSIONS: EGb may have an advantageous properties for health management in elderly and AD sufferers but especially in women with AD. Improving peripheral innate immune cells' activity by adding EGb as accompanying treatment in AD may be, in the long term, a good course to modify the disease progression.

Inhibition of Human Respiratory Influenza A Virus and Human Betacoronavirus-1 by the Blend of Double-Standardized Extracts of Aronia melanocarpa (Michx.) Elliot and Sambucus nigra L.

Viral and bacterial diseases are among the greatest concerns of humankind since ancient times. Despite tremendous pharmacological progress, there is still a need to search for new drugs that could treat or support the healing processes. A rich source of bioactive compounds with antiviral potency include plants such as black chokeberry and elderberry. The aim of this study was to assess the in vitro antiviral ability of an originally designed double-standardized blend of extracts from Aronia melanocarpa (Michx.) Elliot and Sambucus nigra L. (EAM-ESN) or separated extracts of A. melanocarpa (EAM) or S. nigra (ESN) against four human respiratory tract viruses: influenza A virus (A/H1N1), betacoronavirus-1 (HCoV-OC43) belonging to the same ß-coronaviruses as the current pandemic SARS-CoV-2, human herpesvirus type 1 (HHV-1), and human adenovirus type 5 (HAdV-5). Antiviral assays (AVAs) were used to evaluate the antiviral activity of the plant extracts in a cell-present environment with extracts tested before, simultaneously, or after viral infection. The virus replication was assessed using the CPE scale or luminescent assay. The EAM-ESN blend strongly inhibited A/H1N1 replication as well as HCoV-OC43, while having a limited effect against HHV-1 and HAdV-5. This activity likely depends mostly on the presence of the extract of S. nigra. However, the EAM-ESN blend possesses more effective inhibitory activity toward virus replication than its constituent extracts. A post-infection mechanism of action of the EAM-ESN make this blend the most relevant for potential drugs and supportive treatments; thus, the EAM-ESN blend might be considered as a natural remedy in mild, seasonal respiratory viral infections.

Current and Near-Future Treatment of Alzheimer's Disease.

Recent findings have improved our understanding of the multifactorial nature of AD. While in early asymptomatic stages of AD, increased amyloid-ß synthesis and tau hyperphosphorylation play a key role, while in the latter stages of the disease, numerous dysfunctions of homeostatic mechanisms in neurons, glial cells, and cerebrovascular endothelium determine the rate of progression of clinical symptoms. The main driving forces of advanced neurodegeneration include increased inflammatory reactions in neurons and glial cells, oxidative stress, deficiencies in neurotrophic growth and regenerative capacity of neurons, brain insulin resistance with disturbed metabolism in neurons, or reduction of the activity of the Wnt-ß catenin pathway, which should integrate the homeostatic mechanisms of brain tissue. In order to more effectively inhibit the progress of neurodegeneration, combination therapies consisting of drugs that rectify several above-mentioned dysfunctions should be used. It should be noted that many widely-used drugs from various pharmacological groups, "in addition" to the main therapeutic indications, have a beneficial effect on neurodegeneration and may be introduced into clinical practice in combination therapy of AD. There is hope that complex treatment will effectively inhibit the progression of AD and turn it into a slowly progressing chronic disease. Moreover, as the mechanisms of bidirectional communication between the brain and microbiota are better understood, it is expected that these pathways will be harnessed to provide novel methods to enhance health and treat AD.

Inverse Correlation Between Alzheimer's Disease and Cancer: Short Overview.

The negative association between Alzheimer's disease (AD) and cancer suggests that susceptibility to one disease may protect against the other. When biological mechanisms of AD and cancer and relationship between them are understood, the unsolved problem of both diseases which still touches the growing human population could be overcome. Actual information about biological mechanisms and common risk factors such as chronic inflammation, age-related metabolic deregulation, and family history is presented here. Common signaling pathways, e.g., p53, Wnt, role of Pin1, and microRNA, are discussed as well. Much attention is also paid to the potential impact of chronic viral, bacterial, and fungal infections that are responsible for the inflammatory pathway in AD and also play a key role to cancer development. New data about common mechanisms in etiopathology of cancer and neurological diseases suggests new therapeutic strategies. Among them, the use of nilotinib, tyrosine kinase inhibitor, protein kinase C, and bexarotene is the most promising.

Nuclear Envelope and Nuclear Pore Complexes in Neurodegenerative Diseases-New Perspectives for Therapeutic Interventions.

Transport of proteins, transcription factors, and other signaling molecules between the nucleus and cytoplasm is necessary for signal transduction. The study of these transport phenomena is particularly challenging in neurons because of their highly polarized structure. The bidirectional exchange of molecular cargoes across the nuclear envelope (NE) occurs through nuclear pore complexes (NPCs), which are aqueous channels embedded in the nuclear envelope. The NE and NPCs regulate nuclear transport but are also emerging as relevant regulators of chromatin organization and gene expression. The alterations in nuclear transport are regularly identified in affected neurons associated with human neurodegenerative diseases. This review presents insights into the roles played by nuclear transport defects in neurodegenerative disease, focusing primarily on NE proteins and NPCs. The subcellular mislocalization of proteins might be a very desirable means of therapeutic intervention in neurodegenerative disorders.

Metal and bimetallic nanoparticles: Flow synthesis, bioactivity and toxicity.

HYPOTHESIS: Metal nanoparticles are used as additives in commercial products due to their antimicrobial properties. Apart from their high biocidal activity, it is widely observed that silver nanoparticles are toxic. Simultaneously, copper nanoparticles show fungicidal properties, but with limited effectiveness. Hence, it is suggested that a combination of Ag nanoparticles with Cu nanoparticles may decrease the toxic effects of silver while maintaining their high bioactivity. EXPERIMENTS: This paper presents the properties of Ag and Cu metal nanoparticles, and Ag-Cu and Cu-Ag bimetallic nanoparticles, synthesised in a continuous microwave reactor. The size of the metal nanoparticles obtained was in the range of 27-97 nm, and the size of the bimetallic nanoparticles was in the range of 32-184 nm, depending on the microwave irradiation, residence time, pH of the solution and concentrations of the reagents. FINDINGS: Silver nanoparticles of particle size 97 nm revealed the highest antimicrobial activity (MIC = 10 mg/dm3). Simultaneously, silver nanoparticles did not show viral properties, compared to the copper and bimetallic nanoparticles, for which the virus titre was 1.06-1.50 log TCID50/cm3. In contrast to pure metal nanoparticles, the combination of silver and copper in bimetallic systems generated nanoparticles with no genotoxicity (rac(-)/rac(+) < 1.2).

Antitumor effect of baicalin from the Scutellaria baicalensis radix extract in B-acute lymphoblastic leukemia with different chromosomal rearrangements.

Acute B-lymphoblastic leukemia (B-ALL) is the most common hematologic malignancy in children. Many cases of B-ALL harbor chromosomal translocations which are often critical determinants of prognosis. Most of them represent altered transcription factors that impact gene transcription or enhance signaling. B-ALLs harboring the mixed-lineage leukemia 1 (MLL1) gene rearrangements represent aggressive, high-risk type of early childhood leukemias that are usually associated with a very poor prognosis. Therefore, there is an urgent need for novel therapeutic agents as well as new treatment strategies. The objective was to examine the vitro inhibitory effects of Scutellaria baicalensis root extract (SBE) in B-ALL cell lines with different chromosomal rearrangements and in leukemic blasts derived from patients' bone marrow (BMCs). In this study we showed that baicalin which is the main component of the SBE possess antitumor activity against all leukemic cell lines especially those with MLL and PBX1 gene rearrangements. Baicalin inhibited cell proliferation, arrested the cell cycle at the G0/G1 phase, and induced cell death through caspase 3/7 activation. Moreover, baicalin treatment inhibited the glycogen synthase kinase-3ß (GSK-3ß) by suppressing its phosphorylation at Y216, and upregulated the downstream mediator of the cell cycle arrest - cyclin dependent kinase inhibitor p27Kip1. Bone marrow derived blasts from B-ALL patients also exhibited varied sensitivity towards baicalin with 72% patients sensitive to the SBE and baicalin treatment. Taken together, our findings provide new insights into the anti-cancer properties of baicalin by showing its diverse mode of action which might be related to the different genetic background.

Hampering Herpesviruses HHV-1 and HHV-2 Infection by Extract of Ginkgo biloba (EGb) and Its Phytochemical Constituents.

Despite the availability of several anti-herpesviral agents, it should be emphasized that the need for new inhibitors is highly encouraged due to the increasing resistant viral strains as well as complications linked with periods of recurring viral replication and reactivation of latent herpes infection. Extract of Ginkgo biloba (EGb) is a common phytotherapeutics around the world with health benefits. Limited studies, however, have addressed the potential antiviral activities of EGb, including herpesviruses such as Human alphaherpesvirus 1 (HHV-1) and Human alphaherpesvirus 2 (HHV-2). We evaluated the antiviral activity of EGb and its phytochemical constituents: flavonoids and terpenes against HHV-1 and HHV-2. Pretreatment of the herpesviruses with EGb prior to infection of cells produced a remarkable anti-HHV-1 and anti-HHV-2 activity. The extract affected the viruses before adsorption to cell surface at non-cytotoxic concentrations. In this work, through a comprehensive anti-HHV-1 and anti-HHV-2 activity study, it was revealed that flavonoids, especially isorhamnetin, are responsible for the antiviral activity of EGb. Such activity was absent in quercetin and kaempferol. However, EGb showed the most potent antiviral potency compared to isorhamnetin. EGb could augment current therapies for herpes labialis and genital herpes. Moreover, the potential use of EGb in multidrug therapy with synthetic anti-herpes compounds might be considered.

New therapeutic targeting of Alzheimer's disease with the potential use of proline-rich polypeptide complex to modulate an innate immune response - preliminary study.

BACKGROUND: The lack of effective treatment for Alzheimer's disease (AD) stems mainly from the incomplete understanding of AD causes. Neuroinflammation has emerged as an important component of AD pathology, and a vast number of experimental and clinical data indicated a crucial role for the activation of the innate immune system in disease promotion and symptom progression. METHODS: Clinical examinations of AD patients in a different stage of disease severity in correlation with the measurement of two innate immune reactions, i.e., peripheral blood leukocyte (PBLs) resistance to viral infection (vesicular stomatitis virus, VSV) ex vivo, and cytokines: TNF-α, IFN-γ, IL-1ß, and IL-10, production with enzyme-linked immunosorbent assay (ELISA), have been investigated during this preliminary study before and after 4 weeks of oral treatment with dietary supplement proline-rich polypeptide complex (PRP) (120 µg of PRP/day). The potential effect of PRP on the distribution of PBLs' subpopulations has been specified. RESULTS: We have found a deficiency in innate immune response in AD patients. It was demonstrated for the first time that the degree of PBLs resistance to VSV infection was closely related to the stage of clinical severity of AD. Our study showed significant differences in cytokine production which pointed that in AD patients innate immune mechanisms are impaired. Administration of PRP to our patients increased innate immune response of PBLs and declined pro- and anti-inflammatory cytokine production, thus subduing the excessively developed inflammatory response, especially among patients with high severity of AD. PRP did not exhibit a pro-proliferative activity. It was showed, however, significant influence of PRP on the distribution of PBLs' subpopulations. CONCLUSION: The findings mentioned above might be crucial in the context of potential application of immunomodulatory therapy in AD patients and indicated PRP as a potential target for future treatments in neuroinflammatory diseases like AD.

The Gut Microbiome Alterations and Inflammation-Driven Pathogenesis of Alzheimer's Disease-a Critical Review.

One of the most important scientific discoveries of recent years was the disclosure that the intestinal microflora takes part in bidirectional communication between the gut and the brain. Scientists suggest that human gut microflora may even act as the "second brain" and be responsible for neurodegenerative disorders like Alzheimer's disease (AD). Although human-associated microbial communities are generally stable, they can be altered by common human actions and experiences. Enteric bacteria, commensal, and pathogenic microorganisms, may have a major impact on immune system, brain development, and behavior, as they are able to produce several neurotransmitters and neuromodulators like serotonin, kynurenine, catecholamine, etc., as well as amyloids. However, brain destructive mechanisms, that can lead to dementia and AD, start with the intestinal microbiome dysbiosis, development of local and systemic inflammation, and dysregulation of the gut-brain axis. Increased permeability of the gut epithelial barrier results in invasion of different bacteria, viruses, and their neuroactive products that support neuroinflammatory reactions in the brain. It seems that, inflammatory-infectious hypothesis of AD, with the great role of the gut microbiome, starts to gently push into the shadow the amyloid cascade hypothesis that has dominated for decades. It is strongly postulated that AD may begin in the gut, and is closely related to the imbalance of gut microbiota. This is promising area for therapeutic intervention. Modulation of gut microbiota through personalized diet or beneficial microbiota intervention, alter microbial partners and their products including amyloid protein, will probably become a new treatment for AD.

Expression of caspase 1 and histomorphology of lung after cladribine treatment.

BACKGROUND: Cladribine is a useful immunosuppressive drug for the treatment of autoimmune diseases, leukemias and multiple sclerosis (MS). Despite the drug having low toxicity, side effects have been reported connected with myelosuppression, neutropenia and severe anemia. OBJECTIVES: The objective of this study was to investigate the influence of cladribine on lung pathomorphology and the expression of caspase 1 using immunohistochemistry method. MATERIAL AND METHODS: The study was conducted on Wistar rats, which were divided into a control group (C) and an experimental group (E). In group C, the rats were given a 0.9% NaCl solution by a subcutaneous injection, at the same dose as the dose of drug used in the experiment. In group E, the animals received cladribine at a dose of 0.07 mg/kg/24 h by a subcutaneous injection. The animals were decapitated 24 h following the last dose. To detect collagen deposition, we utilized Masson's trichrome staining. To evaluate the intensity of the inflammatory process in the lung, an immunohistochemistry reaction was carried out with the use of caspase 1. RESULTS: In group E, we observed an increase in the thickness of space between the alveoli. A statistically significant (p < 0.017243) difference between the thicknesses of the interalveolar septum was seen between the research groups. In E group, we observed regions with collagen deposition, alveolar epithelial cell hyperplasia, hyperemia and inflammatory cell infiltration. Caspase 1 activity was higher in group E. The immunohistochemical reaction with caspase 1 was positive in 49% of all the interalveolar cells in group E; however, in group C about 13% of the interalveolar cell showed positive immunohistochemistry (IHC) response. CONCLUSIONS: Cladribine-based therapy might have negative influence on lung morphology. The interstitial changes in the lung tissue suggest that cladribine is a drug that may be the cause of drug-induced lung disease and may lead to several respiratory disorders.

CB2R agonist prevents nicotine induced lung fibrosis.

INTRODUCTION: Nicotine stimulates fibroblast proliferation while increasing inflammation and fibrosis of tissues. The cannabinoid receptor 1 (CB1R) is mainly located in the CNS, while cannabinoid receptor 2 (CB2R) is located in the immune cells within the body. CB2R regulates inflammatory processes and fibroblast function. PURPOSE: We investigated the impact of CB2R agonist, JWH 133 and the antagonist, AM630 on lung tissue, applied directly before nicotine application. MATERIAL AND METHODS: 40 mice were placed into 4 groups. The experimental groups received nicotine intraperitoneally at a dose of 0.05 mg/kg of body weight (BW) for 14 days. Group B also received AM630 (0.5mg/kg of BW), while Group A was administered with JWH133 (1 mg/kg of BW). Group N received nicotine alone. The Control group C received 0.9% NaCl. After decapitation, lung tissues were stained with H&E, Trichrome Masson's method, and IHC against CTGF and α-SMA. The digital image processing system Image J with the IHC profiler plugins was then employed, optical density and IHC optical density score were calculated. RESULTS: In the N group, an increase in the thickness of alveolar spaces (9.16 SD4.95µm vs. 4.77SD2.99µm in the C group), leukocytes infiltration and collagen deposition has been observed(OD: 0.20 SD0.0vs 0.07SD0.04 in the C group). In the B group, the alveolar space thickness has been the highest (11.57SD8.13µm). Furthermore, in this group, hyperaemia, destruction of lung structure, hyperplasia of II type pneumocyte and interstitial fibrosis has been observed (OD: 0.23 SD0.08). In contrast, the lung tissue of the A group has had normal structure and the thinnest alveolar septum (3.88 SD2.64µm). The expression of CTGF and α-SMA has been the highest in the B group. CONCLUSION: Nicotine induces interstitial lung fibrosis that is enhanced by the CB2R antagonist and diminished by the CB2R agonist. Therefore, the CB2R agonist may offer a protection against fibrosis.

The Infectious Etiology of Alzheimer's Disease.

BACKGROUND: Inflammation is a part of the first line of defense of the body against invasive pathogens, and plays a crucial role in tissue regeneration and repair. A proper inflammatory response ensures the suitable resolution of inflammation and elimination of harmful stimuli, but when the inflammatory reactions are inappropriate it can lead to damage of the surrounding normal cells. The relationship between infections and Alzheimer's Disease (AD) etiology, especially lateonset AD (LOAD) has been continuously debated over the past three decades. METHODS: This review discusses whether infections could be a causative factor that promotes the progression of AD and summarizes recent investigations associating infectious agents and chronic inflammation with AD. Preventive and therapeutic approaches to AD in the context of an infectious etiology of the disease are also discussed. RESULTS: Emerging evidence supports the hypothesis of the role of neurotropic viruses from the Herpesviridae family, especially Human herpesvirus 1 (HHV-1), Cytomegalovirus (CMV), and Human herpesvirus 2 (HHV-2), in AD neuropathology. Recent investigations also indicate the association between Hepatitis C virus (HCV) infection and dementia. Among bacteria special attention is focused on spirochetes family and on periodontal pathogens such as Porphyromonas gingivalis or Treponema denticola that could cause chronic periodontitis and possibly contribute to the clinical onset of AD. CONCLUSION: Chronic viral, bacterial and fungal infections might be causative factors for the inflammatory pathway in AD.

Association between Periodontal Health Status and Cognitive Abilities. The Role of Cytokine Profile and Systemic Inflammation.

BACKGROUND: Contemporary neurobiology, periodontal medicine, and immunology are now focusing on the relationship between chronic periodontitis and systemic diseases, which also include Alzheimer's disease (AD). However a causative relationship between dementia and periodontitis has yet to be confirmed. OBJECTIVE: The aim of the study was to determine whether periodontal health status and cognitive abilities are correlated with the relative changes in systemic measures of pro- and anti-inflammatory cytokines as a reflection of systemic inflammation. We hypothesized that poor periodontal health status may be associated with cognitive impairment and dementia via the exacerbation of systemic inflammation. METHODS: Based on the periodontal and psychiatric examinations and the cytokine levels produced by unstimulated and LPS-stimulated PBL isolated from 128 participants, we have examined if the coexisting of these two clinically described conditions may have influence on the systemic inflammation. Mini- Mental State Examination (MMSE) and Bleeding on Probing (BoP) test results were combined into the one mathematical function U, which determines the severity of specific condition, called Cognitive and periodontal impairment state. Similarly, the levels of cytokines were combined into the one mathematical function V, whose value determines the level of Inflammatory state. The correlation between U and V was determined. RESULTS: These results confirm that the presence of cognitive decline and the additional source of proinflammatory mediators, like periodontal health problems, aggravate the systemic inflammation. CONCLUSION: It is most likely that the comorbidity of these two disorders may deepen the cognitive impairment, and neurodegenerative lesions and advance to dementia and AD.

Inflammatory Response in the CNS: Friend or Foe?

Inflammatory reactions could be both beneficial and detrimental to the brain, depending on strengths of their activation in various stages of neurodegeneration. Mild activation of microglia and astrocytes usually reveals neuroprotective effects and ameliorates early symptoms of neurodegeneration; for instance, released cytokines help maintain synaptic plasticity and modulate neuronal excitability, and stimulated toll-like receptors (TLRs) promote neurogenesis and neurite outgrowth. However, strong activation of glial cells gives rise to cytokine overexpression/dysregulation, which accelerates neurodegeneration. Altered mutual regulation of p53 protein, a major tumor suppressor, and NF-κB, the major regulator of inflammation, seems to be crucial for the shift from beneficial to detrimental effects of neuroinflammatory reactions in neurodegeneration. Therapeutic intervention in the p53-NF-κB axis and modulation of TLR activity are future challenges to cope with neurodegeneration.