Physical exercise protocols in animal models of Alzheimer's disease: a systematic review.

Several animal studies have showed the beneficial effects of physical exercise (PE) on brain function and health. Alzheimer's Disease (AD) is the most common type of dementia, characterized by the presence of aggregated extracellular amyloid-beta (Aß) and neurofibrillary tangles, with progressive cognitive decline. Therapeutic approaches such as PE showed to be effective in halting AD progression. Here, we present a systematic review about PE and AD. The search was carried out using the PubMed and LILACS databases. The following keywords were used: Alzheimer; PE; animal model. All found studies adopted aerobic exercise training as the PE protocol (100%). We identified running on treadmill as the most commonly used PE routine (62.5%). The duration of each session, intensity, frequency, and period of training most used were 60 min/day (62.5%), moderate intensity (87.5%), 5 days/week (62.5%), and 4 (37.5%) or 12 (37.5%) weeks, respectively. The AD animal models most used were the Tg APP/PS1ΔE9 (25%), models based on i.c.v. infusion of AßOs (25%) and streptozotocin (25%). All protocols used rodents to their experiments (100%), but mice were the most common (62.5%). Finally, the main results presented in all studies were capable to reduce significantly AD consequences, such as reducing Aß or pro-inflammatory proteins levels (100%). The lack of resistance training protocols in animal models of AD indicates a huge gap that should be investigated in future studies. We suggest that PE protocols must be adapted according to the specie, lineage and life span of the animal.

Morphological study of apoptosis in granulosa cells and ovulation in a model of atresia in rat preovulatory follicles.

SummaryPrevious studies have established a model of atresia in preovulatory follicles after stimulation of immature rats with equine chorionic gonadotropin (eCG). This gonadotropin recruits a follicular pool and the deprivation of preovulatory luteinizing hormone (LH) surge induces the atresia in preovulatory follicles. The present study investigated the occurrence of ovulation and provided some morphological features of granulosa cell (GC) apoptosis of atretic follicles at 0, 48, 72 and 120 h after eCG stimulation. Histological sections of ovaries from untreated animals (0 h) showed primordial, primary, secondary and early antral follicles. After 48 h ovaries showed large antral follicles. Preovulatory follicles were observed at 72 h, and two out of five rats displayed cumulus-oocyte complexes (COCs) in the oviducts. All animals exhibited corpora lutea after 120 h. We observed increased estradiol (E2) levels 48 h after eCG treatment that might trigger an endogenous preovulatory gonadotropin surge. Higher progesterone (P4) level, which is the hallmark of a functional corpus luteum, was observed at 120 h. Atresia in secondary and antral follicles was observed by pyknotic granulosa cell nuclei in histology and positive immunolabelling for cleaved caspase 3. We also observed macrophages in secondary and antral follicles in atresia. Transmission electron microscopy revealed GCs with compacted chromatin against the nuclear envelope, nuclear fragmentation, cell shrinkage and fragmentation. No preovulatory follicles showed apoptosis of GCs. In conclusion, our results suggested the occurrence of an endogenous gonadotropin surge, promoting ovulation and preventing atresia of preovulatory follicles.

Detection of SARS-CoV-2 genome on inanimate surfaces in COVID-19 intensive care units and emergency care cohort.

INTRODUCTION: Understanding the different transmission routes of SARS-CoV-2 is crucial in planning effective interventions in healthcare institutions. This study aimed to evaluate the presence of SARS-Cov-2 genome on inanimate surfaces in COVID-19 intensive care unit and emergency care cohorts. METHODS: This is a prospective cross-sectional study. Samples of the environmental surface of objects and furniture were collected between July 15 and October 15, 2020, at COVID-19 intensive and emergency care units. The presence of SARS-CoV-2 genome was determined by quantitative RT-qPCR. The positivity rate for SARS-Cov-2 genome is presented as the arithmetic mean of the sum of the values obtained in each collection. Values of 1.0, 0.5, and 0.0 were assigned for positive, indeterminate, and negative events, respectively. RESULTS: In the intensive care unit, 86% of samples collected at the stethoscope and bed rail surfaces were positive. In the emergency care unit, 43% of bathroom tap, bed rails, and bedside table samples were positive. SARS-CoV-2 genome was not detected at the computer mouse and keyboard. At the emergency care unit, 14.3% of the samples from the collection room armchair were positive. CONCLUSIONS: SARS-CoV-2 genome can be found at the environmental surface of objects and furniture at COVID-19 care units. They can represent a potential source of indirect transmission pathway for COVID-19, especially within health service institutions.

Prior aerobic physical training modulates neuropeptide expression and central thermoregulation after ovariectomy in the rat.

This study compared the effects of aerobic physical training and estradiol (E2) replacement on central pathways involved with thermoregulation in ovariectomized rats. Rats were assigned to untrained ovariectomized treated with placebo (UN-OVX), untrained ovariectomized treated with E2 (E2-OVX), and trained ovariectomized (TR-OVX) groups. Tail skin temperature (TST), internal temperature (Tint), and basal oxygen consumption (VO2) were recorded. Neuronal activity, brain expression of Kiss1, NKB and Prodyn, and central norepinephrine (NE) levels were measured. UN-OVX had the highest TST. Compared to UN-OVX rats, TR-OVX and E2-OVX had lower Fos expression in the paraventricular and arcuate (ARC) nuclei, and lower double labeling for Tyrosine Hydroxylase and Fos in the brainstem. Compared to UN-OVX, only TR-OVX group exhibited lower kisspeptin (Kiss1), neurokinin B (NKB), and prodynorphin expression in the ARC and higher central NE levels. Aerobic physical training before menopause may prevent the heat dissipation imbalance induced by reduction of E2, through central NE release, modulation of Kiss1, NKB and prodynorphin expression in neurons from ARC nucleus.

The superior beneficial effects of exercise training versus hormone replacement therapy on skeletal muscle of ovariectomized rats.

Previous studies have highlighted the positive effects of Estradiol (E2) replacement therapy and physical exercise on skeletal muscle during menopause. However, the comparison effects of exercise training (ET) and estradiol replacement therapy during menopause on skeletal muscle have not been investigated to date. This study aimed to compare the effects of endurance exercise training versus E2 replacement therapy on mitochondrial density, redox status, and inflammatory biomarkers in the skeletal muscle of ovariectomized rats. Thirty female Wistar rats (12-week-old) were randomly assigned into three groups: Untrained ovariectomized rats (UN-OVX, n = 10); untrained ovariectomized rats treated with estradiol replacement therapy (E2-OVX); and, trained ovariectomized rats (TR-OVX). After ovariectomy, the E2-OVX rats were treated subcutaneously with E2 (implanted Silastic® capsule containing 360 µg of 17ß-estradiol/mL) while the TR-OVX group performed an exercise training protocol (50-70% of maximal running speed on a treadmill, 60 min/day, 5 days/week for 8 weeks). After euthanasia, the soleus muscle was processed for histological and biochemical evaluations. Only exercise prevented the reduction of maximal oxygen consumption and increased mechanical efficiency (ME). While mitochondrial muscle density, total antioxidant capacity (FRAP), catalase (CAT) activity, and interleukin 10 levels were higher in TR-OVX, only OVX-E2 presented higher CAT activity and lower interleukin 6 levels. Endurance exercise training compared with E2 replacement therapy maintains the aerobic capacity improving the ME of OVX rats. In addition, only endurance exercise training raises the skeletal muscle mitochondrial content and tends to balance the redox and inflammatory status in the skeletal muscle of OVX rats.

Does endurance training prior to ovariectomy protect against myocardial contractility dysfunction in rats?

BACKGROUND: Endurance training prevents cardiac dysfunction induced by menopause, but to date, no studies compared the effects of endurance training prior to menopause versus estrogen replacement therapy during menopause on heart function of rats. METHODS: Female Wistar rats aged three months were randomly assigned into three groups: Untrained ovariectomized rats (UN-OVX), untrained ovariectomized rats treated with estradiol (UN-OVX-E2), and ovariectomized rats previously exercised (EX-OVX). The endurance training protocol consisted of running on a treadmill at 60-70% of maximal aerobic capacity, 60 min per day, five days per week, for eight weeks. Estradiol replacement therapy consisted of silastic capsules containing the hormone for twelve days. After euthanasia, hearts were harvested, weighed and cardiac function was evaluated by the Langendorff technique. RESULTS: Both cardiac contractility and relaxation indexes improved similarly in the EX-OVX and UN-OVX-E2 rats compared to UN-OVX. CONCLUSION: Our findings reveal similar beneficial effects between endurance training previously to menopause and estradiol replacement therapy during menopause on cardiac function of rats.

Cardioprotective effects of severe calorie restriction from birth in adult ovariectomized rats.

AIMS: Menopause is a female condition induced by a reduction of ovarian hormone and is related to an increase in cardiovascular diseases in women. We have shown that severe calorie restriction (SCR) from birth reduces the cardiometabolic risk in adult male Wistar rats. In this study, we investigated the effects of SCR from birth to adulthood on cardiovascular function of ovariectomized rats. MAIN METHODS: From birth to adulthood, rats were daily fed ad libitum (control group - C) or with 50% of the amount consumed by the control group (calorie-restricted group - R). At 90 days, half of the rats in each group underwent bilateral ovariectomy (OVX), totaling 4 groups: C-Sham, C-OVX, R-Sham, R-OVX. Systolic blood pressure (SBP), heart rate (HR) and, double product (DP) index were recorded by tail-cuff plethysmography. Cardiac function was analyzed by the Langendorff technique and cardiomyocyte diameter was accessed by histologic analysis. Additionally, cardiac SERCA2 content and redox status were evaluated. KEY FINDINGS: C-OVX rats exhibited reduced cardiac function and cardiac non-enzymatic total antioxidant capacity (TAC). R-Sham animals showed reduced SBP, DP, HR, improved cardiac function, reduced cardiac protein carbonyl derivatives and increased TAC, catalase, and superoxide dismutase activities. R-OVX rats maintained reduced SBP, DP, HR, and increased contractility and relaxation indexes. R-Sham and R-OVX rats exhibited preserved heart mass and reduced cardiomyocyte diameter. Cardiac SERCA2 content did not differ between the groups. SIGNIFICANCE: Taken together, our findings show cardioprotective effects of SCR from birth in adult ovariectomized rats.

Estratégia de saúde familiar no Brasil: análise microbiológica na sala de vacinação / Family health strategy in Brazil: microbiological analysis in the vaccination room / Estrategia de salud familiar en Brasil: análisis microbiológico en la sala de vacunación

Enquadramento: As unidades de Estratégia Saúde da Família (ESF) são uma referência no atendimento primário à população, tendo as salas de vacinação como principal procura do serviço. É importante destacar que uma higienização inadequada desse ambiente, apresenta maior probabilidade de causar infeções aos pacientes. Objetivo: Verificar a associação entre a contaminação microbiológica e a assistência prestada na sala de vacinação de uma ESF no Brasil. Metodologia: Estudo descritivo e exploratório, com amostragem para 3 superfícies da sala de vacinação. Resultados: Os resultados evidenciaram 58 unidades formadoras de colónias (UFC), para bactérias e fungos, na agulha de vacina, mais de 300 UFC de bactérias, nas amostras da geladeira e mesa, e mais de 300 UFC de fungos nos mesmos locais. Conclusão: Neste estudo foi possível observar falhas da higienização na sala de vacinação, através do crescimento microbiológico, sugerindo que uma higienização inadequada influencia na assistência prestada, tornando necessárias ações estratégicas que visem a melhoria da qualidade e segurança na sala de vacinação.

Background: The Family Health Strategy (FHS) units are a standard in primary health care to the populations, and vaccination rooms have the highest attendance of the service. It is important to highlight that inadequate hygiene of this environment is more likely to cause infections to patients. Objective: To assess the association between the microbiological contamination and the assistance provided in the vaccination room of a Brazilian FHS unit. Methodology: Descriptive and exploratory study with sampling for three surfaces in the vaccination room. Results: The results showed 58 colony-forming units (CFU), for bacteria and fungi, in the vaccine needle, more than 300 CFU of bacteria in the samples from the fridge and table, and more than 300 CFU of fungi in the same locations. Conclusion: In this study, an inadequate sanitization was observed in the vaccination room, as shown by the microbiological growth. This suggests that inadequate hygiene impacts the care provided, so strategies are necessary for the improvement of quality and safety in the vaccination room.

Marco contextual: Las unidades Estratégicas de Salud Familiar (ESF) son una referencia en la atención primaria a la población, y las salas de vacunación son la principal demanda del servicio. Es importante destacar que una higiene inadecuada de este entorno aumenta la probabilidad de causar infecciones a los pacientes. Objetivo: Comprobar la asociación entre la contaminación microbiológica y la asistencia prestada en la sala de vacunación de una ESF en Brasil. Metodología: Estudio descriptivo y exploratorio, con muestreo de 3 superficies de la sala de vacunación. Resultados: Los resultados mostraron 58 unidades en las que se formaron colonias (UFC) de bacterias y hongos en la aguja de la vacuna, más de 300 UFC de bacterias en las muestras de la nevera y la mesa, y más de 300 UFC de hongos en los mismos lugares. Conclusión: En este estudio se pudieron observar fallos en la higiene de la sala de vacunación, a través del crecimiento microbiológico, lo que sugiere que la higiene inadecuada influye en la asistencia prestada, por lo que es necesario adoptar medidas estratégicas para mejorar la calidad y la seguridad en la sala de vacunación.