Potential antidepressant effects of a dietary supplement from the chlorella and lion's mane mushroom complex in aged SAMP8 mice.

Since the 1990s, the prevalence of mental illnesses, such as depression, has been increasing annually and has become a major burden on society. Due to the many side effects of antidepressant drugs, the development of a complementary therapy from natural materials is an urgent need. Therefore, this study used a complex extract of chlorella and lion's mane mushroom and evaluated its antidepressant effects. Six-month-old male senescence-accelerated mice prone-8 (SAMP8) were divided into positive control; negative control; and low, medium, and high-dose groups. All groups were treated with corticosterone (CORT) at 40 mg/Kg/day for 21- days to induce depression in the animals, and the effects of different test substances on animal behavior was observed. The positive control group was intraperitoneally injected with a tricyclic antidepressant (Fluoxetine, as tricyclic antidepressant), the control group was given ddH2O, and the test substance groups were administered test samples once daily for 21 days. The open field test (OFT) and forced swimming test (FST) were applied for behavior analyses of depression animal models. The OFT results showed that the mice in the positive control and the medium-, and high-dose groups demonstrated a significantly prolonged duration in the central area and a significantly increased travel distance. In the FST, the positive control and the medium, and high-dose groups displayed significantly reduced immobility times relative to the control group. The blood analysis results showed significant decreases in triglyceride and blood urea nitrogen levels relative to the positive control and the medium- and high-dose groups. Notably, in the positive control and the medium- and high-dose groups, brain-derived neurotrophic factor (BDNF) increase by more than in the control group. In summary, medium and high dose of extract of chlorella and lion's mane mushroom could improve depression behavior in animals and have the potential to be antidepressant health care products.

Purification and Identification of Angiotensin I-Converting Enzyme Inhibitory Peptides and the Antihypertensive Effect of Chlorella sorokiniana Protein Hydrolysates.

Hot water was used to obtain Chlorella sorokiniana hot water extract (HWE). Subsequently, this byproduct was freeze-dried, hydrolysed at 50 °C using Protease N to obtain C. sorokiniana protein hydrolysates (PN-1), and then digested with a gastrointestinal enzyme (PN-1G). The inhibitory effects of the HWE and hydrolysates against angiotensin I-converting enzyme (ACE) were investigated. The soluble protein and peptide contents were 379.9 and 179.7 mg/g, respectively, for HWE and 574.8 and 332.8 mg/g, respectively, for PN-1. The IC50 values of the HWE, PN-1, and PN-1G on ACE were 1.070, 0.035, and 0.044 mg/mL, respectively. PN-1G was separated into seven fractions through size exclusion chromatography. The sixth fraction of the hydrolysate had a molecular weight between 270 and 340 Da, and the lowest IC50 value on ACE was 0.015 mg/mL. The amino acid sequences of the ACE-inhibitory peptides were Trp-Val, Val-Trp, Ile-Trp, and Leu-Trp, of which the IC50 values were 307.61, 0.58, 0.50, and 1.11 µΜ, respectively. Systolic blood pressure and diastolic blood pressure were reduced 20 and 21 mm Hg, respectively, in spontaneously hypertensive rats after 6 h of oral administration with a dose of 171.4 mg PN-1 powder/kg body weight.

Immunostimulatory bioactivity of algal polysaccharides from Chlorella pyrenoidosa activates macrophages via Toll-like receptor 4.

Much research suggests that a dietary supplement of Chlorella pyrenoidosa may be helpful to human health, but the molecular mechanism involved remains unclear. The aim of this research was to investigate the effects of certain hot-water-soluble polysaccharides from Chlorella pyrenoidosa (CWSP) on cytokine production, human leukocyte antigen (HLA) expression, and costimulatory molecule expression in macrophages. We demonstrated that CWSP induced IL-1beta secretion in macrophages via Toll-like receptor 4 (TLR4) mediated protein kinase signaling pathways. In addition, CWSP also stimulated the cell surface expression of HLA-DA, -DB, and -DC, and HLA-DR, -DP, and -DQ as well as the expression of costimulatory family molecules such as CD80 and CD86 in macrophages. Furthermore, we demonstrated that preinjection of C57BL/6J mice with CWSP increased lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha and IL-1beta secretion into serum in vivo. This outcome was consistent with the corresponding outcome for cells treated with CWSP in vitro. Our current results provide support for the possible use of CWSP as a modulation agent of immune responses in humans and certain animal species. Finally, in using GC-MS to analyze the polysaccharides, we found that the major monosaccharides of CWSP were rhamnose (31.8%), glucose (20.42%), galactose (10.28%), mannose (5.23%), and xylose (1.27%). This study is the first to report the molecular mechanism of immune-modulated signal transduction in vitro from the polysaccharides of Chlorella pyrenoidosa.