RESUMEN
Recent human cohort studies reported positive associations between organic food consumption and a lower incidence of obesity, cancer, and several other diseases. However, there are very few animal and human dietary intervention studies that provide supporting evidence or a mechanistic understanding of these associations. Here we report results from a two-generation, dietary intervention study with male Wistar rats to identify the effects of feeds made from organic and conventional crops on growth, hormonal, and immune system parameters that are known to affect the risk of a number of chronic, non-communicable diseases in animals and humans. A 2 × 2 factorial design was used to separate the effects of contrasting crop protection methods (use or non-use of synthetic chemical pesticides) and fertilizers (mineral nitrogen, phosphorus and potassium (NPK) fertilizers vs. manure use) applied in conventional and organic crop production. Conventional, pesticide-based crop protection resulted in significantly lower fiber, polyphenol, flavonoid, and lutein, but higher lipid, aldicarb, and diquat concentrations in animal feeds. Conventional, mineral NPK-based fertilization resulted in significantly lower polyphenol, but higher cadmium and protein concentrations in feeds. Feed composition differences resulting from the use of pesticides and/or mineral NPK-fertilizer had a significant effect on feed intake, weight gain, plasma hormone, and immunoglobulin concentrations, and lymphocyte proliferation in both generations of rats and in the second generation also on the body weight at weaning. Results suggest that relatively small changes in dietary intakes of (a) protein, lipids, and fiber, (b) toxic and/or endocrine-disrupting pesticides and metals, and (c) polyphenols and other antioxidants (resulting from pesticide and/or mineral NPK-fertilizer use) had complex and often interactive effects on endocrine, immune systems and growth parameters in rats. However, the physiological responses to contrasting feed composition/intake profiles differed substantially between the first and second generations of rats. This may indicate epigenetic programming and/or the generation of "adaptive" phenotypes and should be investigated further.
Asunto(s)
Agricultura/métodos , Producción de Cultivos , Dieta , Alimentos Orgánicos , Alimentación Animal/análisis , Animales , Cadmio , Productos Agrícolas/química , Ingestión de Alimentos , Granjas , Femenino , Fertilizantes , Humanos , Masculino , Estiércol , Nitrógeno , Plaguicidas , Fenotipo , Fósforo , Potasio , Ratas Wistar , Reino UnidoRESUMEN
Majority of the physiological processes in the human organism are rhythmic. The most common are the diurnal changes that repeat roughly every 24 hours, called circadian rhythms. Circadian rhythms disorders have negative influence on human functioning. The aim of this article is to present the current understanding of the circadian rhythms physiological role, with particular emphasis on the circadian rhythm sleep-wake disorders (CRSWD), principles of their diagnosis and chronobiological therapy. The guidelines are based on the review of recommendations from the scientific societies involved in sleep medicine and the clinical experiences of the authors. Researchers participating in the preparation of guidelines were invited by the Polish Sleep Research Society and the Section of Biological Psychiatry of the Polish Psychiatric Association, based on their significant contributions in circadian rhythm research and/or clinical experience in the treatment of such disorders. Finally, the guidelines were adjusted to the questions and comments given by the members of both Societies. CRSWD have a significant negative impact on human health and functioning. Standard methods used to assess CRSWD are sleep diaries and sleep logs, while the actigraphy, when available, should be also used. The most effective methods of CRSWD treatment are melatonin administration and light therapy. Behavioral interventions are also recommended. Afourteen-day period of sleep-wake rhythm assessment in CRSWD enables accurate diagnosis, adequate selection of chronobiological interventions, and planning adequate diurnal timing of their application. This type of assessment is quite easy, low-cost, and provides valuable indications how to adjust the therapeutic approach to the circadian phase of the particular patient.
Asunto(s)
Ritmo Circadiano , Guías de Práctica Clínica como Asunto/normas , Trastornos del Sueño del Ritmo Circadiano/diagnóstico , Trastornos del Sueño del Ritmo Circadiano/terapia , Investigación Biomédica/normas , Promoción de la Salud/normas , Humanos , Polonia , Medicina del Sueño , Sociedades Médicas/normasRESUMEN
AIM: Circadian rhythm sleep-wake disorders (CRSWD) are a group of disorders, in which the timing of sleep and wakefulness significantly differs from a patient's expectations or socially acceptable times. The aimof the article is to present the current principles for the diagnosis and treatment of CRSWD in adults and children. METHOD: Guidelines proposed as CRSWD treatment standard are based on the recommendations from the scientific societies involved in the sleep research and medicine. Researchers participating in the guidelines preparation were invited by the Polish Sleep Research Society and the Section of Biological Psychiatry of the Polish Psychiatric Association based on their significant contribution to the circadian rhythm research and/or clinical experience in the treatment of these disorders. Finally, the guidelines were adjusted to the questions and comments given by the members of both Societies. RESULTS: Patients with endogenous CRSWD are often misdiagnosed and treated for insomnia or hypersomnia. Therefore, each patient reporting sleep-wake disorders should be interviewed about the quality of sleep and its timing during free days (e.g. weekends, holidays). Avalid CRSWD diagnosis can be also established by using sleep diaries/logs and actigraphy. The treatment of choice for CRSWD is chronotherapy, which involves melatonin application, light therapy, and behavioral interventions. Sleep disorders associated with shift work and time zone changes are a growing health problem. Interventions for these disorders should primarily focus on prevention. CONCLUSIONS: The main problem in the treatment of CRSWD is an invalid diagnosis. Hypnotics and/or psychostimulants are often used instead of chronotherapeutic interventions, what can alleviate symptoms but is not an effective treatment.
Asunto(s)
Guías de Práctica Clínica como Asunto , Trastornos del Sueño del Ritmo Circadiano/diagnóstico , Trastornos del Sueño del Ritmo Circadiano/terapia , Investigación Biomédica , Ritmo Circadiano , Promoción de la Salud/normas , Humanos , Polonia , Medicina del Sueño/normas , Sociedades Médicas/normasRESUMEN
Demand for organic milk is partially driven by consumer perceptions that it is more nutritious. However, there is still considerable uncertainty over whether the use of organic production standards affects milk quality. Here we report results of meta-analyses based on 170 published studies comparing the nutrient content of organic and conventional bovine milk. There were no significant differences in total SFA and MUFA concentrations between organic and conventional milk. However, concentrations of total PUFA and n-3 PUFA were significantly higher in organic milk, by an estimated 7 (95 % CI -1, 15) % and 56 (95 % CI 38, 74) %, respectively. Concentrations of α-linolenic acid (ALA), very long-chain n-3 fatty acids (EPA+DPA+DHA) and conjugated linoleic acid were also significantly higher in organic milk, by an 69 (95 % CI 53, 84) %, 57 (95 % CI 27, 87) % and 41 (95 % CI 14, 68) %, respectively. As there were no significant differences in total n-6 PUFA and linoleic acid (LA) concentrations, the n-6:n-3 and LA:ALA ratios were lower in organic milk, by an estimated 71 (95 % CI -122, -20) % and 93 (95 % CI -116, -70) %. It is concluded that organic bovine milk has a more desirable fatty acid composition than conventional milk. Meta-analyses also showed that organic milk has significantly higher α-tocopherol and Fe, but lower I and Se concentrations. Redundancy analysis of data from a large cross-European milk quality survey indicates that the higher grazing/conserved forage intakes in organic systems were the main reason for milk composition differences.
Asunto(s)
Grasas Insaturadas en la Dieta/análisis , Ácidos Grasos Omega-3/análisis , Alimentos Orgánicos/análisis , Hierro de la Dieta/análisis , Ácidos Linoleicos Conjugados/análisis , Leche/química , alfa-Tocoferol/análisis , Animales , Bovinos , Industria Lechera , Práctica Clínica Basada en la Evidencia , Humanos , Yodo/análisis , Ganado , Valor Nutritivo , Selenio/análisisRESUMEN
The avian pineal gland, apart from the hypothalamic master clock (suprachiasmatic nuclei, SCN) and retina, functions as an independent circadian oscillator, receiving external photic cues that it translates into the rhythmical synthesis of melatonin, a biochemical signal of darkness. Functional similarity to the mammalian SCN makes the avian pineal gland a convenient model for studies on biological clock mechanisms in general. Pineal melatonin is produced not only in a light-dependent manner but also remains under the control of the endogenous oscillator, while the possible involvement of melatonin in maintaining cyclic expression of the avian clock genes remains to be elucidated. The aim of the present study was to characterize the diurnal profiles of main clock genes transcription in the pineal glands of chickens exposed to continuous light (LL) and supplemented with exogenous melatonin. We hypothesized that rearing chickens from the day of hatch under LL conditions would evoke a functional pinealectomy, influencing, in turn, pineal clock function. To verify this hypothesis, we examined the diurnal transcriptional profiles of selected clock genes as well as the essential parameters of pineal gland function: transcription of the genes encoding arylalkylamine N-acetyltransferase (Aanat), a key enzyme in melatonin biosynthesis, and the melatonin receptor (Mel1c), along with the blood melatonin level. Chickens hatched in summer or winter were maintained under LD 16:8 and 8:16, corresponding to the respective photoperiods, as the seasonal control groups. Another set of chickens was kept in parallel under LL conditions and some were supplemented with melatonin to check the ability of exogenous hormone to antagonize the effects evoked by continuous light. Twelve-day-old chickens were sacrificed every 3 h over a 24-h period and the mRNAs of selected clock genes, Bmal1, Cry1, Per3, E4bp4, together with those of Aanat and Mel1c, were quantified in the isolated pineal glands. Our results indicate that the profiles of clock gene transcription are not dependent on the duration of the light phase, while LL conditions decrease the amplitude of diurnal changes, but do not abolish them entirely. Melatonin supplied in drinking water to the birds kept in LL seems to desynchronize transcription of the majority of clock genes in the summer, while in the winter, it restores the pattern, but not the diurnal rhythmicity. Rhythmic expression of Bmal1 appears to provide a direct link between the circadian clock and the melatonin output pathway, while the availability of cyclic melatonin is clearly involved in the canonical transcription pattern of Per3 in the chicken pineal gland. Regardless of the experimental conditions, a negative correlation was identified between the transcription of genes involved in melatonin biosynthesis (Aanat) and melatonin signal perception (Mel1c receptor).
Asunto(s)
Relojes Biológicos , Melatonina/fisiología , Fotoperiodo , Glándula Pineal/fisiología , Acetiltransferasas/metabolismo , Animales , Pollos , Regulación hacia Abajo , Luz , Masculino , Melatonina/sangre , Glándula Pineal/metabolismo , Radioinmunoensayo , Receptores de Melatonina/metabolismo , Estaciones del Año , Factores de Tiempo , Transcripción GenéticaRESUMEN
Tea tree oil (TTO) is well known as an antimicrobial and immunomodulatory agent. In the present study we confirmed the anti-inflammatory properties of TTO and investigated the involvement of the hypothalamic-pituitary-adrenal (HPA) axis in the immunomodulatory action of TTO administered by inhalation. Sexually mature, 6-8-week-old, C(57)BI(10) x CBA/H (F(1)) male mice were used. One group of animals was injected intra-peritoneally (ip) with Zymosan to elicit peritoneal inflammation and was then submitted to four sessions of TTO inhalation (15 mins each). Some of the mice were simultaneously injected ip with Antalarmin, a CRH-1 receptor antagonist, to block HPA axis functions. Twenty-four hours after the injections the mice were killed by CO(2) asphyxia, and peritoneal leukocytes (PTLs) were isolated and counted. Levels of reactive oxygen species (ROS) and cyclooxygenase (COX) activity in PTLs were assessed by fluorimetric and colorimetric assays, respectively. The results obtained show that sessions of TTO inhalation exert a strong anti-inflammatory influence on the immune system stimulated by Zymosan injection, while having no influence on PTL number, ROS level, and COX activity in mice without inflammation. The HPA axis was shown to mediate the anti-inflammatory effect of TTO; Antalarmin abolished the influence of inhaled TTO on PTL number and their ROS production in mice with experimental peritonitis, but it had no effect on these parameters in mice without inflammation.
Asunto(s)
Antiinflamatorios/farmacología , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Aceite de Árbol de Té/farmacología , Administración por Inhalación , Animales , Antiinflamatorios/administración & dosificación , Recuento de Células , Inhibidores de la Ciclooxigenasa/farmacología , Sistema Hipotálamo-Hipofisario/inmunología , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/farmacología , Leucocitos/citología , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Modelos Biológicos , Cavidad Peritoneal/citología , Sistema Hipófiso-Suprarrenal/inmunología , Prostaglandina-Endoperóxido Sintasas/metabolismo , Pirimidinas/farmacología , Pirroles/farmacología , Especies Reactivas de Oxígeno/metabolismo , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Aceite de Árbol de Té/administración & dosificación , Acetato de Tetradecanoilforbol/farmacología , Tiofenos/farmacología , Zimosan/administración & dosificación , Zimosan/farmacologíaRESUMEN
The immunomodulatory properties of melatonin (Mel) are generally recognized but the mechanisms of its action are not fully understood. In mammals, some of the immunomodulatory effects of Mel are mediated by opioids synthesized by immune cells under its influence. The present study was performed to examine whether Mel-induced opioids are involved in the immunomodulatory activity of Mel in chickens. Experimental peritonitis was evoked by a single ip injection of thioglycollate (TG), and half of the birds were pre-treated with Mel. Some of the Mel-treated birds were additionally pre-treated with naltrexone, an antagonist of opioid receptors. Control birds received an injection of saline, Mel or were untreated. At specific post-injection intervals chickens were sacrificed, the peritoneal cavity was flushed out and peritoneal leukocytes (PTLs) were counted. The activity of PTLs was measured in vitro by the level of reactive oxygen species (ROS). Splenocytes were isolated aseptically and mitogen-stimulated in vitro proliferation was assessed. In PTLs and splenocytes the expression of opioid (proopiomelanocortin and proenkephalin) genes was also examined. Mel exerted a bi-phasic effect on TG-induced peritonitis in chickens: initially it blocked the development of peritonitis, decreasing the number of PTLs and intracellular ROS level (anti-inflammatory action), and thereafter an increase in both PTL number and ROS level was observed (pro-inflammatory action). The pro-inflammatory effect occurred a few hours after the induction of expression of the proenkephalin gene in PTLs and both the proenkephalin and proopiomelanocortin genes in splenocytes. These effects were prevented by naltrexone, suggesting involvement of the opiatergic mechanism.