Effects of quercetin on predator stress-related hematological and behavioural alterations in pregnant rats and their offspring

A short pre-conception bout of predation risk affects both children and grandchildren

Traumatic events that affect physiology and behavior in the current generation may also impact future generations. We demonstrate that an ecologically realistic degree of predation risk prior to conception causes lasting changes in the first filial (F1) and second filial (F2) generations. We exposed male and female mice to a live rat (predator stress) or control (non-predator) condition for 5 min. Ten days later, stressed males and females were bred together as were control males and females. Adult F1 offspring from preconception-stressed parents responded to a mild stressor with more anxiety-like behavior and hyperarousal than offspring from control parents. Exposing these F1 offspring to the mild stressor increased neuronal activity (cFOS) in the hippocampus and altered glucocorticoid system function peripherally (plasma corticosterone levels). Even without the mild stressor, F1 offspring from preconception-stressed parents still exhibited more anxiety-like behaviors than controls. Cross-fostering studies confirmed that preconception stress, not maternal social environment, determined offspring behavioral phenotype. The effects of preconception parental stress were also unexpectedly persistent and produced similar behavioral phenotypes in the F2 offspring. Our data illustrate that a surprisingly small amount of preconception predator stress alters the brain, physiology, and behavior of future generations. A better understanding of the 'long shadow' cast by fearful events is critical for understanding the adaptive costs and benefits of transgenerational plasticity. It also suggests the intriguing possibility that similar risk-induced changes are the rule rather than the exception in free-living organisms, and that such multigenerational impacts are as ubiquitous as they are cryptic.

Substitution of raw lucerne with raw citrus lemon by-product in silage: In vitro apparent digestibility and gas production

Fruit pomace addition to lucerne silage could rapidly reduce silage pH creating an acidic environment and thus maybe preventing spoilage. However, the purpose of this study was to investigate the effect of different rates of inclusion of citrus lemon by-products on lucerne. In this study, the following five different treatments were prepared: L0 (control) with 100% lucerne; L25 (75% lucerne with 25% lemon pomace); L50 (50% lucerne with 50% lemon pomace); L75 (25% lucerne with 75% lemon pomace); and L100 (100% lemon pomace). After ensiling, the chemical composition, nutritive value, stability, in vitro apparent digestibility, and gas production of silage were determined. The dry matter (DM) content was higher for lemon pomace substitution equal to or exceeded 50% (P < 0.01). Crude protein, on the contrary, decreased (P < 0.01) over the same percentage of substitution. The L100 and L75 treatments showed higher DM apparent disappearance rate and lower (P < 0.05) crude protein and neutral detergent fiber apparent degradation rate vs. L0. Lemon pomace could be used at high inclusion level in lucerne silage, allowing the preservation of this by-product all the year, improving some chemical silage characteristics, and reducing proteolytic processes that usually happen on lucerne silage. Moreover, the in vitro apparent digestibility and gas production results showed that a partial substitution of lucerne with lemon pomace is able to improve silage digestibility.

Perinatal diet and offspring anxiety: A scoping review

Health behaviors during pregnancy have an impact on the developing offspring. Dietary factors play a role in the development of mental illness: however, less is known about the impact of diet factors during pre-conception, gestation, and lactation on anxiety levels in offspring. This scoping review sought to systematically map the available research involving human and animal subjects to identify nutritional interventions which may have a harmful or protective effect, as well as identify gaps. Studies investigating an association between any perinatal diet pattern or diet constituent and offspring anxiety were included. The number of studies reporting an association with increased or decreased levels of anxiety were counted and presented in figures. A total of 55,914 results were identified as part of a larger scoping review, and 120 articles met the criteria for inclusion. A greater intake of phytochemicals and vitamins were associated with decreased offspring anxiety whereas maternal caloric restriction, protein restriction, reduced omega-3 consumption, and exposure to a high fat diet were associated with higher levels of offspring anxiety. Results were limited by a very large proportion of animal studies. High quality intervention studies involving human subjects are warranted to elucidate the precise dietary factors or constituents that modulate the risk of anxiety in offspring.

Quercetin attenuates reduced uterine perfusion pressure -induced hypertension in pregnant rats through regulation of endothelin-1 and endothelin-1 type A receptor

BACKGROUND

Quercetin was reported to be crucial for a broad range of activities, including attenuating inflammation, platelet aggregation, capillary permeability, and lipid peroxidation. However, the effect of quercetin in hypertension during pregnancy, was not fully understood.

METHODS

The model of hypertension in pregnancy was established in rats by reduced uterine perfusion pressure (RUPP). Quercetin was administrated by gavage. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using the CODA 6 BP system. Plasma concentrations of Endothelin-1 (ET-1), soluble fms-like tyrosine kinase-1 (sFlt-1), and vascular endothelial growth factor (VEGF) were detected using enzyme-linked immunosorbent assay kits. The mRNA and protein levels of ET-1 and endothelin-1 type A receptor (ETAR) were determined by RT-PCR and Western blotting. The ETAR antagonist BQ-123 was performed by osmotic minipumps.

RESULTS

In RUPP induced rats, quercetin treatment decreased SBP and DBP, fetal resorptions percentage, plasma ET-1 and sFlt-1 concentrations, ET-1 and ETAR levels, but increased fetal body weight and VEGF expression. BQ-123 administration attenuated SBP and DBP, suppressed fatal resorptions percentage, and increased fetal body weight of RUPP rats.

CONCLUSION

Quercetin attenuates RUPP induced hypertension in pregnant rats through the regulation of ET-1 and ETAR.

Quercetin attenuates acute predator stress exposure-evoked innate fear and behavioral perturbation

Background Oxidative stress plays a pivotal role in the pathophysiology and pathogenesis of mental diseases, such as depression or anxiety. Psychological stress induced by predatory stimulus is one of the models that explain how induced affective behavior is manifested as a depression-like state. Quercetin is a flavonoid that exhibits potential pharmacological activity on mental diseases. Thus, the present study was designed to investigate the effect of quercetin on innate fear and affective behavior induced by repeated predator stress exposure on mice. Materials and methods ICR mice were exposed to predatory stress for 3 days. Quercetin at a dose of 50 mg/kg was given intraperitoneally along with stress induction. The freezing behavior during the stress induction was analyzed. The anxiety-like and depressive-like behaviors and cognitive and motor functions were examined on the last day of induction. Results Predatory stress increased the affective behaviors (anxiety-like and depressive-like behaviors) and produced freezing behavior without alterations in the cognitive function and exploratory behavior. Treatment with quercetin 50 mg/kg attenuated the freezing, anxiety-like and depressive-like behaviors. Conclusions Repeated predator stress exposure causes both innate fear and depression-like state for the prey animals. Quercetin may have a protective effect against depression and alleviates the fear of traumatic events.

Pharmacological Effect of Quercetin in Hypertension and Its Potential Application in Pregnancy-Induced Hypertension: Review of In Vitro, In Vivo, and Clinical Studies

Since improving maternal and child health is a public health priority worldwide, the main aim of treatment of hypertension in pregnant women is to prevent complications during pregnancy, labor, and postpartum. In consequence, much attention is paid to the use of antihypertensive drugs that can be used safely during pregnancy. Several side effects of methyldopa, which is currently the most commonly used antihypertensive drug in pregnant women, mean that the search for an effective and safe alternative still continues. Flavonoid compounds present in medicinal plants, vegetables, and fruits may be a promising source of new drugs. In this aspect, quercetin, a well-known flavonoid due to its antihypertensive action, may be considered a prototype for safe antihypertensive drugs. This review focuses on the selective activity of quercetin. Based on recent studies, a few problems were discussed, including (1) pathology of pregnancy-induced hypertension; (2) search for new pharmacological treatments of pregnancy-induced hypertension; (3) issues with the use of herbal extracts during pregnancy; (4) flavonoids as natural active chemical compounds; (5) quercetin: its action during pregnancy, in vitro and in vivo pharmacological activities, clinical trials, and meta-analysis; (6) quercetin intake during pregnancy; (7) other natural compounds tested during pregnancy; (8) potential problems with the use of quercetin; (9) safety profile of quercetin. Various studies have shown a beneficial effect of quercetin on vascular endothelial function and its antioxidative and anti-inflammatory activity on cellular and tissue level. It is known that in animal models quercetin affects positively the development of embryo, fetus, and placenta. Because this flavonoid did not have teratogenic and abortive effect, it is generally recognized as safe. For this reason it should be appreciated and studied in the aspect of its potential use in the prevention and treatment of pregnancy-induced hypertension among women in this risk group.

Chemo-mapping and biochemical-modulatory and antioxidant/prooxidant effect of Galium verum extract during acute restraint and dark stress in female rats

Galium verum is a well-known medicinal plant which is used in various pathologies. G. verum extracts are characterized here using chromatography, where among the rich pool of phenolic acids of flavonoids two known anti-stress modulators, chlorogenic acid and rutin are identified in high quantities. Additionally, the extracts are characterized using a series of in vitro assays (EPR, DPPH, TPC and TEAC). Considering the chemical findings, the potential beneficial effects of the G. verum extract are explored here in a living organism exposed to stress induced oxidative damages. Thus, the biochemical-modulatory and antioxidant roles of two doses of G. verum extract are examined in animals exposed to acute restraint and dark stress (S). The animals were divided in groups [control, S, SG1 (exposed to 25 mg G. verum extract), SG2 (50 mg extract)]. Increased levels of lipid peroxidation (TBARS from 4.43 to 8.06 nmol/mL), corticosterone from 0.43 to 1.96 μg/dL and epinephrine from 44.43 to 126.7 μg/mL, as well as decreased antioxidant enzymes activities (SOD/CAT) were observed in the S group. The G. verum extract afforded a near-normal equilibrium within the biochemical parameters of animals exposed to RS, by reducing oxidative damage (TBARS at a 3.73 nmol/mL; CS at 0.90 μg/dL; EP at 63.72 μg/mL) and by restoring the antioxidant balance.

Post 6-OHDA lesion exposure to stress affects neurotrophic factor expression and aggravates motor impairment

Chronic exposure to stress amplifies locomotor deficits and exacerbates dopamine neuron loss in an animal model for Parkinson's disease. The release of neurotrophic factors such as glial cell-line derived neurotrophic factor (GDNF) and neurotrophin-3 (NT-3) following neuronal injury attenuates exacerbated degeneration of these neurons. In this study, the neurotoxin 6-hydroxydopamine (6-OHDA) was injected unilaterally into the medial forebrain bundle of male Sprague Dawley rats. A subset of these rats was subjected to post-lesion restraint stress after which the effect of exposure to stress on locomotor activity (forelimb akinesia test), neurotrophic factor (GDNF and NT-3) and corticosterone concentration was assessed. Exposure to post-lesion stress resulted in increased preference to use the unimpaired forelimb (forelimb ipsilateral to the lesioned hemisphere) in the forelimb akinesia test. The expected increase in both GDNF and NT-3 concentration following injury was not present in the stressed animals. However, both the non-stressed and stressed lesioned groups had decreased neurotrophic factor concentration at one and two weeks post lesion. This decrease was exaggerated in the stressed rats. The decrease in neurotrophic factor concentration was accompanied by an increase in corticosterone concentration in the stressed rats. These findings demonstrate that exposure to post-6-OHDA lesion stress exaggerates dopamine neurodegeneration and enhance motor impairment. This suggests that conditions that result in a hyper-activated hypothalamic-pituitary-adrenal axis such as depression which is concomitant to a Parkinson's disease diagnosis may be responsible for enhanced dopamine depletion by attenuating neurotrophic factor concentration elevation in the nigrostriatal pathway following neuronal injury.