Neuroinflammation, immune system and Alzheimer disease: searching for the missing link.

Due to an increasingly aging population, Alzheimer disease (AD) represents a crucial issue for the healthcare system because of its widespread prevalence and the burden of its care needs. Several hypotheses on AD pathogenesis have been proposed and current therapeutical strategies have shown limited effectiveness. In the last decade, more evidence has supported a role for neuroinflammation and immune system dysregulation in AD. It remains unclear whether astrocytes, microglia and immune cells influence disease onset, progression or both. Amyloid-ß peptides that aggregate extracellularly in the typical neuritic plaques generate a constant inflammatory environment. This causes a prolonged activation of microglial and astroglial cells that potentiate neuronal damage and provoke the alteration of the blood brain barrier (BBB), damaging the permeability of blood vessels. Recent data support the role of the BBB as a link between neuroinflammation, the immune system and AD. Hence, a thorough investigation of the neuroinflammatory and immune system pathways that impact neurodegeneration and novel exciting findings such as microglia-derived microvesicles, inflammasomes and signalosomes will ultimately enhance our understanding of the pathological process. Eventually, we should proceed with caution in defining a causal or consequential role of neuroinflammation in AD, but rather focus on identifying its exact pathological contribution.

Diagnosis and treatment of acute pharyngitis/tonsillitis: a preliminary observational study in General Medicine.

OBJECTIVE: According to recent observations, the insufficiently targeted use of antibiotics is creating increasingly resistant bacterial strains. In this context, it seems increasingly clear the need to resort to extreme and prudent rationalization of antibiotic therapy, especially by the physicians working in primary care units. In clinical practice, actually the general practitioner often treats multiple diseases without having the proper equipment. In particular, the use of a dedicated, easy to use diagnostic test would be one more weapon for the correct diagnosis and treatment of acute pharyngo-tonsillitis. The disease is a condition frequently encountered in clinical practice but its optimal management remains a controversial topic. In this context, the observational study is intended to demonstrate the usefulness of the rapid test (RAD: Rapid antigen detection) against group A beta-hemolytic streptococcus (GABHS) in everyday clinical practice to identify individuals with acute streptococcal pharyngo-tonsillitis needing antibiotic therapy and to pursue the following objectives: (1) Getting the answer to an unmet medical need; (2) Promoting the appropriateness of the use of antibiotics; (3) Provide a means of containment in pharmaceutical spending. PATIENTS AND METHODS: 50 patients presenting sore throat associated with erythema and/or pharyngeal tonsillar exudate with or without scarlatiniform rash, fever and malaise had been subjected to perform a rapid test (RAD: Rapid antigen detection) for the search of the beta-hemolytic Streptococcus Group A (GABHS). Pharyngeal-tonsillar swabs were tested using Immunospark (relative sensitivity 97.6%, relative specificity 97.5%) according to manufacturer's instructions (runtime/reading response < 10 min). RESULTS: Of the 50 tests, 45 provided a negative response while 5 were positive for the search of the beta-hemolytic Streptococcus group A. No test result has been invalid. CONCLUSIONS: Based on the results obtained, only patients with a positive rapid test were subjected to targeted antibiotic therapy. This has resulted in a significant cost savings in pharmaceutical expenditure, without neglecting the more important and correct application of the Guidelines with performing of a clinically validated test that carries advantages for reducing the use of unnecessary and potentially harmful antibiotics and the consequent lower prevalence and incidence of antibiotic-resistant bacterial strains.

A Systematic Review on the Effects of Botanicals on Skeletal Muscle Health in Order to Prevent Sarcopenia.

We performed a systematic review to evaluate the evidence-based medicine regarding the main botanical extracts and their nutraceutical compounds correlated to skeletal muscle health in order to identify novel strategies that effectively attenuate skeletal muscle loss and enhance muscle function and to improve the quality of life of older subjects. This review contains all eligible studies from 2010 to 2015 and included 57 publications. We focused our attention on effects of botanical extracts on growth and health of muscle and divided these effects into five categories: anti-inflammation, muscle damage prevention, antifatigue, muscle atrophy prevention, and muscle regeneration and differentiation.

Use of the FLUKA Monte Carlo code for 3D patient-specific dosimetry on PET-CT and SPECT-CT images.

Patient-specific absorbed dose calculation for nuclear medicine therapy is a topic of increasing interest. 3D dosimetry at the voxel level is one of the major improvements for the development of more accurate calculation techniques, as compared to the standard dosimetry at the organ level. This study aims to use the FLUKA Monte Carlo code to perform patient-specific 3D dosimetry through direct Monte Carlo simulation on PET-CT and SPECT-CT images. To this aim, dedicated routines were developed in the FLUKA environment. Two sets of simulations were performed on model and phantom images. Firstly, the correct handling of PET and SPECT images was tested under the assumption of homogeneous water medium by comparing FLUKA results with those obtained with the voxel kernel convolution method and with other Monte Carlo-based tools developed to the same purpose (the EGS-based 3D-RD software and the MCNP5-based MCID). Afterwards, the correct integration of the PET/SPECT and CT information was tested, performing direct simulations on PET/CT images for both homogeneous (water) and non-homogeneous (water with air, lung and bone inserts) phantoms. Comparison was performed with the other Monte Carlo tools performing direct simulation as well. The absorbed dose maps were compared at the voxel level. In the case of homogeneous water, by simulating 10(8) primary particles a 2% average difference with respect to the kernel convolution method was achieved; such difference was lower than the statistical uncertainty affecting the FLUKA results. The agreement with the other tools was within 3­4%, partially ascribable to the differences among the simulation algorithms. Including the CT-based density map, the average difference was always within 4% irrespective of the medium (water, air, bone), except for a maximum 6% value when comparing FLUKA and 3D-RD in air. The results confirmed that the routines were properly developed, opening the way for the use of FLUKA for patient-specific, image-based dosimetry in nuclear medicine.

Kidney dosimetry in ¹77Lu and 9°Y peptide receptor radionuclide therapy: influence of image timing, time-activity integration method, and risk factors.

Kidney dosimetry in (177)Lu and (90)Y PRRT requires 3 to 6 whole-body/SPECT scans to extrapolate the peptide kinetics, and it is considered time and resource consuming. We investigated the most adequate timing for imaging and time-activity interpolating curve, as well as the performance of a simplified dosimetry, by means of just 1-2 scans. Finally the influence of risk factors and of the peptide (DOTATOC versus DOTATATE) is considered. 28 patients treated at first cycle with (177)Lu DOTATATE and 30 with (177)Lu DOTATOC underwent SPECT scans at 2 and 6 hours, 1, 2, and 3 days after the radiopharmaceutical injection. Dose was calculated with our simplified method, as well as the ones most used in the clinic, that is, trapezoids, monoexponential, and biexponential functions. The same was done skipping the 6 h and the 3 d points. We found that data should be collected until 100 h for (177)Lu therapy and 70 h for (90)Y therapy, otherwise the dose calculation is strongly influenced by the curve interpolating the data and should be carefully chosen. Risk factors (hypertension, diabetes) cause a rather statistically significant 20% increase in dose (t-test, P < 0.10), with DOTATATE affecting an increase of 25% compared to DOTATOC (t-test, P < 0.05).

Mitochondrial alterations, oxidative stress and neuroinflammation in Alzheimer's disease.

Alzheimer's disease (AD) is a multifactorial disorder characterized by the progressive deterioration of neuronal networks. The primary cause and sequence of its progression are only partially understood but abnormalities in folding and accumulation of insoluble proteins such as beta-amyloid and Tau-protein are both associated with the pathogenesis of AD. Mitochondria play a crucial role in cell survival and death, and changes in mitochondrial structure and/or function are related to many human diseases. Increasing evidence suggests that compromised mitochondrial function contributes to the aging process and thus may increase the risk of AD. Dysfunctional mitochondria contribute to reactive oxygen species which can lead to extensive macromolecule oxidative damage and the progression of amyloid pathology. Oxidative stress and amyloid toxicity leave neurons chemically vulnerable. The mitochondrial toxicity induced by beta-amyloid is still not clear but may include numerous mechanisms, such as the increased permeability of mitochondrial membranes, the disruption of calcium homeostasis, the alteration of oxidative phosphorylation with a consequent overproduction of reactive oxygen species. Other mechanisms have been associated with the pathophysiology of AD. Inflammatory changes are observed in AD brain overall, particularly at the amyloid deposits, which are rich in activated microglia. Once stimulated, the microglia release a wide variety of pro-inflammatory mediators including cytokines, complement components and free radicals, all of which potentially contribute to further neuronal dysfunction and eventually death. Clinically, novel approaches to visualize early neuroinflammation in the human brain are needed to improve the monitoring and control of therapeutic strategies that target inflammatory and other pathological mechanisms. Similarly, there is growing interest in developing agents that modulate mitochondrial function.

Alzheimer's disease, autoimmunity and inflammation. The good, the bad and the ugly.

Alzheimer's disease (AD) has been recognized as the most common cause of sporadic dementia. It represents both a medical and social problem, as it affects 10% of over-65 population. Even if the elderly are the most involved population, aging alone cannot be considered as the only cause of this disease. In this review we wanted to focus on the last hypotheses on the possible causes of this neuronal affection. We focused in particular on the role of inflammation and alteration of the inflammatory status that is typical of the elderly and may lead to chronic inflammation. The inflammation seems to be a cause of neuronal impairment and loss. Some studies have proposed a protective role of antiinflammatory drugs. Then we analyzed the role of genetic polymorphisms of some pro-inflammatory substances that seem to be linked to some cases of dementia. The complement system seems to have a role too, as some factors have been found in senile plaques, representing a possible involvement of classical complement pathway. One of the latest hypotheses is about the role of blood-brain barrier (BBB), as its loss of integrity may lead to a passage of proteins in cerebro spinal fluid (CSF), causing a compromised role of BBB in preserving the brain as an "immune sanctuary".

[Markers of brain injury in non-invasive biological fluids]. / Markers of brain injury in non-invasive biological fluids.

Hypoxia-ischemia (H-I) constitutes the main phenomenon responsible for brain-blood barrier permeability modifications leading to cerebral vascular autoregulation loss in newborns. Hypotension, cerebral ischemia, and reperfusion are the main events involved in vascular auto-regulation loss leading to cell death and tissue damage. Reperfusion could be critical since organ damage, particularly of the brain, may be amplified during this period. An exaggerated activation of vasoactive agents, of calcium mediated effects could be responsible for reperfusion injury (R-I), which, in turns, leads to cerebral hemorrhage and damage. These phenomena represent a common repertoire in newborns complicated by perinatal acute or chronic hypoxia treated by risky procedures such as mechanical ventilation, nitric oxide supplementation, brain cooling, and extracorporeal membrane oxygenation (ECMO). Despite accurate monitoring, the post-insult period is crucial, as clinical symptoms and standard monitoring parameters may be silent at a time when brain damage is already occurring and the therapeutic window for pharmacological intervention is limited. Therefore, the measurement of circulating biochemical markers of brain damage, such as vasoactive agents and nervous tissue peptides is eagerly awaited in clinical practice to detect high risk newborns. The present article is aimed at investigating the role of dosage biochemical markers in non-invasive biological fluids such as S100B, a calcium binding protein, activin A, a protein expressed in Central nervous System (CNS).

Growth factors decrease in subjects with mild to moderate Alzheimer's disease (AD): potential correction with dehydroepiandrosterone-sulphate (DHEAS).

The integrity of neuroprotection is an important component against the development of cognitive disorders and AD. Within this context, DHEAS would seem to have some positive metabolic and endocrine effects to delay brain aging by recovering the impairment of neuroprotective growth factors. In the present study we measured by ELISA the secretion of insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF), and transforming growth factor-beta1 (TGFbeta1) in the supernatants of cultured circulating peripheral blood mononuclear cells (PBMC) from which natural killer cells (NK) were separated (PBMC-NK) (pg/ml/7.75x10(6) cells) in healthy subjects and in age-matched patients with mild to moderate AD. The growth factors were measured in spontaneous conditions and after stimulation with growth hormone (GH) 1 microg/ml (IGF-1), lipopolysaccharide (LPS) 1 microg/ml (VEGF) and glucose 10 microM (TGF(beta1). AD group demonstrated at baseline a severe reduction of IGF-1 (3.7+1.2 pg/ml after GH), VEGF (63+/-18 pg/ml spontaneous and 210+/-65 pg/ml after LPS) and TGF(beta1 (33+/-10 pg/ml spontaneous and 75+/-12 pg/ml after glucose) secretions compared to healthy elderly subjects (IGF-1, 9.5+/-2.8 pg/ml after GH, p<0.001; VEGF, 117+/-38 pg/ml spontaneous, p<0.001 and 690+/-120 pg/ml after LPS, p<0.001; and TGF(beta1, 73+/-21 pg/ml spontaneous, p<0.001 and 169+/-53 pg/ml after glucose, p<0.001). Significant positive correlations between IGF-1 and VEGF concentrations were found both in healthy subjects (r=0.87, p<0.001) and in AD subjects (r=0.87, p<0.001). The co-incubation of NK cells with DHEAS (10(6) M/ml/cells) significantly increase IGF-1, VEGF and TGF (beta1 production, reaching in AD group the normal concentrations found in healthy subjects (IGF-1, 7.9 + 2.4 pg/ml after GH; VEGF, 105+/-31 pg/ml spontaneous and 670+/-112 pg/ml after LPS; and TGFfbeta1, 68+/-18 pg/ml spontaneous and 155+/-48 pg/ml after glucose). These data suggested that DHEAS is able to increase the immunoendocrine production of neuroprotective growth factors, which is reduced in AD subjects, so suggesting a new approach in the treatment of dementia.

Implementation of a primary screen for developmental neurotoxicity.

A battery of tests to evaluate physical growth/development and neurobehavioral function was conducted with 78 litters of control Sprague-Dawley rats given purified water by intubation. The objectives of this study were to optimize test methods and to document the range and variability of the experimental endpoints. Data are presented for maternal evaluations (body weight gain, food consumption), gestation length, litter size, and postnatal survival. Pup body weight was used to assess postnatal somatic growth rate from birth to 85 days of age, while whole and regional brain weight measurements at 7, 28, and 85 days provided a more specific measure of physical growth relevant to a neurobehavioral study. Physical landmarks of development evaluated were pinna unfolding, incisor eruption, and eye opening while reflex landmarks of development evaluated were the negative geotaxis and pupillary reflexes. The mean percentage of litters acquiring a physical trait or reflex increased sigmoidally with age, and the data suggest that the potential to detect developmental delays would be optimal when ca. 90% of control litters reach the test landmark. Functional evaluations were arranged according to four testing subsets so that each litter was evaluated in each test (1 pup/sex/litter), but repeated testing on pups was minimized. Auditory and tactile startle reflexes, as well as prepulse inhibition, were measured at ages 22 days and 60-64 days and found to increase with age. A passive avoidance paradigm (age 40-43 days) was used to assess exploratory behavior (approach) and memory (avoidance). Swimming performance in a water maze was used to evaluate learning. In this test, escape times and error rates improved to their highest level by five or six trials and showed acceptable degrees of variability. Spontaneous motor activity was monitored for 23 hr at age 54-61 days to evaluate exploratory activity, photoperiod entrainment, and catecholamine-induced locomotion (amphetamine challenge). Finally, landmarks of sexual maturation (balanopreputial separation evident at 45 days of age, vaginal perforation evident at 33 days) and estrous cyclicity (4.8 cycles per 21 days) were evaluated as measures of reproductive neuroendocrine function. In sum, the test battery provided an efficient yet comprehensive screen for evaluating effects on physical growth/development and neurobehavioral function which meets practical criteria for preclinical testing of pharmaceutical agents.

Relative cerebellar weight: a potential indicator of developmental neurotoxicity.

Overt malformations do not always accompany behavioral changes resulting from perinatal exposure to certain drugs. However, the central nervous system (CNS) is the anatomical substrate for behavior, and functional defects may be accompanied by more subtle, structural alterations of the brain. The purpose of this study was to determine if changes in the weights of certain brain regions occur in rats exposed prenatally and/or perinatally to propylthiouracil (PTU) which retards functional development of the brain. Pregnant rats were dosed with PTU during gestation and/or lactation, and on postnatal day 28, auditory startle responses were measured to determine if PTU altered functional development. The brains of all pups were then dissected into 10 separate regions, dried and individually weighed. Brain weights were expressed in absolute and relative (to total brain weight) terms. Pups that were exposed to PTU from days 10 to 21 of gestation grew normally, but their startle responses to auditory stimuli were significantly different (p less than 0.05) from controls. Thus, for the purpose of this experiment, PTU acted as a developmental neurotoxicant because it altered performance on a test of neuromuscular function without being overtly teratogenic. The weights of most brain regions in PTU-treated rats were statistically comparable to controls. However, relative cerebellar weight was significantly (p less than 0.05) different. Therefore, these data suggested that relative cerebellar weight might be used to predict functional defects that appear during development following prenatal or perinatal exposure to certain neurotoxicants. Although cerebellar weight and auditory startle responses were altered by PTU, this study does not establish a causal relationship between the anatomical and functional changes that occurred.(ABSTRACT TRUNCATED AT 250 WORDS)

Design of a primary screen for developmental neurotoxicity.

A battery of tests was devised for routine use as a primary screen for developmental neurotoxicity. The battery was divided into preweaning and postweaning tests using rats as subjects. Since the rat CNS is structurally incomplete at birth, preweaning tests were predominantly physical, using specific landmarks of somatic maturation and regional brain growth as indices of normal development. Pupillary responses to light and positional responses to gravity (negative geotaxis) were also included in the preweaning battery to monitor reflex behavior, a relatively simple CNS function. The postweaning battery predominantly contained functional tests to evaluate higher order behaviors that develop after completion of neurogenesis. The postweaning tests were divided into 4 subsets designed to evaluate (I) neuromuscular function, (II) memory, (III) problem solving, and (IV) neuroendocrine function, respectively. Curiosity, rhythmicity, patency of monoamine neurons, and physical measures of brain growth were included within the subsets so as to evaluate a spectrum of CNS functions. Preliminary findings suggest that tests and instrumentation selected for the proposed battery provide an informative, objective, comprehensive and cost-efficient means to screen for developmental neurotoxicity.

Lack of in vivo mutagenicity and testicular toxicity of triamterene in mice.

Triamterene (2,4,7-triamino-6-phenylpteridine), a widely used diuretic/antihypertensive agent with weak antifolate activity, has been found to be positive in several in vitro assays for mutagenicity. The present studies were undertaken to characterize the potential mutagenic and antifolate activity of triamterene in the bone marrow and testes of mice with in vivo treatment. Triamterene had no clastogenic effects on the bone marrow at 6, 16, or 24 hr after a single oral dose of 25, 125, or 250 mg/kg. No alterations in hematopoietic cell maturation characteristic of antifolate action were observed in a dose-range study in which triamterene was orally administered to mice at 5-300 mg/kg/day for 5 days. Triamterene had no adverse effects on mating or fertility and did not induce dominant lethal mutations in the germ cells of male mice when given for 5 days at 5-100 mg/kg/day. Oral exposure to mice under identical conditions had no effect on testicular weight, DNA content, or activity of the de novo pathway for thymidine synthesis from deoxy [6-3H]uridine. The present findings are consistent with an absence of mutagenic effect and antifolate action on the bone marrow and testes with in vivo administration.

Effect of benzodiazepines on age of vaginal perforation and first estrus in mice.

Female mice which received chlordiazepoxide, diazepam, oxazepam, prazepam, flurazepam, or nitrazepam prenatally and postnatally had delays in the age of vaginal perforation and first estrus concomitant with reduced postnatal growth. Females exposed prenatally showed no growth deficits, but in four treatments had delayed vaginal opening. However, the age of first estrus was generally less than the control.