Low temperature-aged garlic extract suppresses psychological stress by modulation of stress hormones and oxidative stress response in brain

Structural Characteristics and Immunomodulatory Effects of Melanoidins from Black Garlic

Melanoidins are considered to have several biological activities. In this study, black garlic melanoidins (MLDs) were collected using ethanol solution extraction; 0%, 20%, and 40% ethanol solutions were used for chromatography. Three kinds of melanoidins were produced by macroporous resin, named MLD-0, MLD-20, and MLD-40. The molecular weight was determined, and the infrared and microscopic structures were studied. In addition, Balb/c mice were induced with cyclophosphamide (CTX) to establish an immune deficiency model to evaluate the immune efficacy of black garlic melanoidins (MLDs). The results showed that MLDs restored the proliferation and phagocytosis ability of macrophages, and the proliferation activity of B lymphocytes in the MD group was 63.32% (♀) and 58.11% (♂) higher than that in the CTX group, respectively. In addition, MLDs alleviated the abnormal expression of serum factors such as IFN-γ, IL-10, and TNF-α. 16SrDNA sequencing of intestinal fecal samples of mice showed that MLDs changed the structure and quantity of intestinal flora, and especially that the relative abundance of Bacteroidaceae was significantly increased. The relative abundance of Staphylococcaceae was significantly reduced. These results showed that MLDs improved the diversity of intestinal flora in mice, and improved the adverse state of immune organs and immune cells. The experiments confirm that black garlic melanoidins have potential value in immune activity, which provides an important basis for the development and utilization of melioidosis.

The poorly conducted orchestra of steroid hormones, oxidative stress and inflammation in frailty needs a maestro: Regular physical exercise

This review outlines the various factors associated with unhealthy aging which includes becoming frail and dependent. With many people not engaging in recommended exercise, facilitators and barriers to engage with exercise must be investigated to promote exercise uptake and adherence over the lifespan for different demographics, including the old, less affluent, women, and those with different cultural-ethnic backgrounds. Governmental and locally funded public health messages and environmental facilitation (gyms, parks etc.) can play an important role. Studies have shown that exercise can act as a conductor to balance oxidative stress, immune and endocrine functions together to promote healthy aging and reduce the risk for age-related morbidities, such as cardiovascular disease and atherosclerosis, and promote cognition and mood over the lifespan. Like a classic symphony orchestra, consisting of four groups of related musical instruments - the woodwinds, brass, percussion, and strings - the aging process should also perform in harmony, with compassion, avoiding the aggrandizement of any of its individual parts during the presentation. This review discusses the wide variety of molecular, cellular and endocrine mechanisms (focusing on the steroid balance) underlying this process and their interrelationships.

Neuroprotective effects of garlic extract on dopaminergic neurons of substantia nigra in a rat model of Parkinson's disease: motor and non-motor outcomes

Parkinson's disease (PD) is a common and severe neurodegenerative disorder associated with a selective loss of dopaminergic neurons in substantia nigra pars compacta. The crucial role of oxidative stress and inflammation in PD onset and progression is evident. It has been proven that garlic extract (GE) protects the cells from oxidative stress, inflammation, mitochondrial dysfunction and apoptosis. That is, we aimed to investigate if GE reveals protective features on the preclinical model of PD. The study has been designed to evaluate both preventive (GE administered before 6-OHDA injection) and therapeutic (GE administered after 6-OHDA injection) effects of GE on the animal model. Forty male Wistar rats were divided into 4 groups including control, lesion, treatment I (received GE before 6-OHDA injection) and treatment II (received GE both before and after 6-OHDA injection). At the end of treatment, hanging, rotarod, open field and passive avoidance tests as well as immunohistochemistry were performed to evaluate the neuroprotective effects of garlic against PD. Our immunohistochemistry analysis revealed that the tyrosine hydroxylase positive cells (TH+) in GE treated groups were significantly higher (p˂0.001) than the lesion group. The motor deficiency significantly improved in hanging, rotarod, open-field and apomorphine-induced rotational tests. We observed an attenuation in memory impairment induced by PD on GE treated group. Therefore, we found that GE protects dopaminergic neurons in 6-OHDA-induced neurotoxicity and ameliorates movement disorders and behavioral deficits.

Neuroprotective Natural Products for Alzheimer's Disease

Alzheimer's disease (AD) is the number one neurovegetative disease, but its treatment options are relatively few and ineffective. In efforts to discover new strategies for AD therapy, natural products have aroused interest in the research community and in the pharmaceutical industry for their neuroprotective activity, targeting different pathological mechanisms associated with AD. A wide variety of natural products from different origins have been evaluated preclinically and clinically for their neuroprotective mechanisms in preventing and attenuating the multifactorial pathologies of AD. This review mainly focuses on the possible neuroprotective mechanisms from natural products that may be beneficial in AD treatment and the natural product mixtures or extracts from different sources that have demonstrated neuroprotective activity in preclinical and/or clinical studies. It is believed that natural product mixtures or extracts containing multiple bioactive compounds that can work additively or synergistically to exhibit multiple neuroprotective mechanisms might be an effective approach in AD drug discovery.

Mustard Leaf Extract Suppresses Psychological Stress in Chronic Restraint Stress-Subjected Mice by Regulation of Stress Hormone, Neurotransmitters, and Apoptosis

Mustard leaf (Brassica juncea var. crispifolia L. H. Bailey) has been reported to have psychological properties such as anti-depressant activities. However, studies on chronic stress and depression caused by restraint have not been conducted. Therefore, this study aimed to evaluate the effects of a mustard leaf (ML) extract on chronic restraint stress (CRS) in mice. Male mice were subjected to a CRS protocol for a period of four weeks to induce stress. The results showed that the ML extract (100 and 500 mg/kg/perorally administered for four weeks) significantly decreased corticosterone levels and increased neurotransmitters levels in stressed mice. Apoptosis by CRS exposure was induced by Bcl-2 and Bax expression regulation and was suppressed by reducing caspase-3 and poly (ADP-ribose) polymerase expression after treatment with the ML extract. Our results confirmed that apoptosis was regulated by increased expression of brain-derived neurotrophic factor (BDNF). Additionally, cytokine levels were regulated by the ML extract. In conclusion, our results showed that the ML extract relieved stress effects by regulating hormones and neurotransmitters in CRS mice, BDNF expression, and apoptosis in the brain. Thus, it can be suggested that the studied ML extract is an agonist that can help relieve stress and depression.

Exploring the anti-stress effects of imatinib and tetrabenazine in cold-water immersion-induced acute stress in mice

The aim of the present study was to explore the ameliorative role of imatinib and tetrabenazine in acute stress-induced behavioural and biochemical changes in mice. Cold-water immersion (5 min duration) was employed to induce acute stress and the resulting changes in the locomotor activity, exploratory behaviour, motor activity and social behaviour were assessed using the actophotometer, the hole board, the open field and the social interaction tests. The biochemical alterations were assessed by measuring the plasma corticosterone levels using ELISA kit. Cold-water immersion-induced acute stress diminished the locomotor activity, exploratory behaviour, motor activity and social behaviour along with increase in the plasma corticosterone levels. Administration of imatinib (50 and 100 mg/kg, i.p.), a tyrosine kinase inhibitor, significantly attenuated the cold-water immersion-induced behavioural alterations with normalization of the plasma corticosterone levels in a dose-dependent manner. Moreover, administration of tetrabenazine (1 and 2 mg/kg, i.p.), a vesicular monoamine transporter 2 (VMAT2) inhibitor, also abolished the acute stress-induced behavioural and biochemical changes in a dose-dependent manner. The beneficial effects of imatinib and tetrabenazine in normalizing acute stress-induced biochemical and behavioural changes make them promising therapeutic agents in the treatment of acute stress-related problems.