Effect of a Standardized Extract of Asparagus officinalis Stem (ETAS®50) on Cognitive Function, Psychological Symptoms, and Behavior in Patients with Dementia: A Randomized Crossover Trial

Dementia is a disease of substantial national concern in a superaging society in Japan. Thus, the treatments targeting this disease are of high priority. However, pharmaceutical treatments are under development and invasive. Hence, many alternative treatments, which are less invasive, are tried, and some of them are supposed to work for dementia symptoms. ETAS®50 is one of these treatments. ETAS®50, a standardized extract of the Asparagus officinalis stem with heat shock protein-inducing activity, is a functional food. ETAS®50 has antistress, autonomic nerve regulation, and sleep quality improvement effects in humans and could contribute to relieving dementia symptoms. This double-blind crossover pilot trial aimed to examine the effects of ETAS®50. A total of 27 patients with mild-to-moderate dementia between October 2018 and February 2020 were included in the trial. ETAS®50 was consumed for 12 weeks and then a placebo for 12 weeks. A significant difference in the mean score of the severity of symptoms in the Neuropsychiatric Inventory Questionnaire (NPI-Q-a) was observed between the ETAS®50 period (0.56 ± 1.72 points) and placebo period (-0.67 ± 2.34 points) (p=0.045). Between-group comparisons with respect to the items of NPI-Q-a also showed a significant decrease in symptoms in the ETAS®50 period compared with the placebo period (p=0.015 for agitation and p=0.045 for depression). In addition, we observed that scores for apathy tended to improve in the ETAS®50 period (p=0.058).

Standardized Extract of Asparagus officinalis Stem Attenuates SARS-CoV-2 Spike Protein-Induced IL-6 and IL-1β Production by Suppressing p44/42 MAPK and Akt Phosphorylation in Murine Primary Macrophages

Excessive host inflammation following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with severity and mortality in coronavirus disease 2019 (COVID-19). We recently reported that the SARS-CoV-2 spike protein S1 subunit (S1) induces pro-inflammatory responses by activating toll-like receptor 4 (TLR4) signaling in macrophages. A standardized extract of Asparagus officinalis stem (EAS) is a unique functional food that elicits anti-photoaging effects by suppressing pro-inflammatory signaling in hydrogen peroxide and ultraviolet B-exposed skin fibroblasts. To elucidate its potential in preventing excessive inflammation in COVID-19, we examined the effects of EAS on pro-inflammatory responses in S1-stimulated macrophages. Murine peritoneal exudate macrophages were co-treated with EAS and S1. Concentrations and mRNA levels of pro-inflammatory cytokines were assessed using enzyme-linked immunosorbent assay and reverse transcription and real-time polymerase chain reaction, respectively. Expression and phosphorylation levels of signaling proteins were analyzed using western blotting and fluorescence immunomicroscopy. EAS significantly attenuated S1-induced secretion of interleukin (IL)-6 in a concentration-dependent manner without reducing cell viability. EAS also markedly suppressed the S1-induced transcription of IL-6 and IL-1β. However, among the TLR4 signaling proteins, EAS did not affect the degradation of inhibitor κBα, nuclear translocation of nuclear factor-κB p65 subunit, and phosphorylation of c-Jun N-terminal kinase p54 subunit after S1 exposure. In contrast, EAS significantly suppressed S1-induced phosphorylation of p44/42 mitogen-activated protein kinase (MAPK) and Akt. Attenuation of S1-induced transcription of IL-6 and IL-1β by the MAPK kinase inhibitor U0126 was greater than that by the Akt inhibitor perifosine, and the effects were potentiated by simultaneous treatment with both inhibitors. These results suggest that EAS attenuates S1-induced IL-6 and IL-1β production by suppressing p44/42 MAPK and Akt signaling in macrophages. Therefore, EAS may be beneficial in regulating excessive inflammation in patients with COVID-19.

Enzyme-treated Asparagus Extract (ETAS) Enhances Memory in Normal Rats and Induces Neurite-outgrowth in PC12 Cells

Enzyme-treated asparagus extract (ETAS) contains various phytochemicals. It has been reported that ETAS protected early cognitive impairment of SAMP8 mice and Aβ-induced reduction of PC12 cell viability. In addition, ETAS had several functions on healthy people. The purpose of the present study was to investigate the effects of ETAS on normal memory function of rats and neurite-outgrowth of PC12 cells. ETAS significantly accelerated learning acquisition in in vivo and neurite-outgrowth in in vitro study. In conclusion, ETAS affected on memory function in early stage in normal rats. The basis of this effect may induce neurite-outgrowth in neurons.

Enzyme-Treated Asparagus Extract Prevents Hydrogen Peroxide-Induced Pro-Inflammatory Responses by Suppressing p65 Nuclear Translocation in Skin L929 Fibroblasts

We recently reported that enzyme-treated asparagus extract (ETAS) attenuates hydrogen peroxide (H2O2)-stimulated matrix metalloproteinase-9 expression in skin fibroblast L929 cells. To further elucidate the anti-aging effects of ETAS on skin, we examined whether ETAS has preventive effects on H2O2-induced pro-inflammatory responses of skin fibroblasts. H2O2 induced Ser536 phosphorylation and nuclear accumulation of nuclear factor-κB (NF-κB) p65, and increased the mRNA levels of interleukin-12α (IL-12α) and inducible nitric oxide synthase (iNOS) in L929 cells. Pretreatment of the cells with JSH-23, an inhibitor of NF-κB nuclear translocation, abolished the H2O2-induced expression of IL-12α and iNOS, indicating that the increased transcription is regulated by p65. The H2O2-stimulated nuclear accumulation of p65 and induction of IL-12α and iNOS mRNA were significantly attenuated after pretreatment with ETAS for 3 h, and these responses were completely abolished when the duration was extended to 24 h. However, ETAS did not affect the H2O2-stimulated degradation of IκBα and phosphorylation of p65. On the other hand, ETAS treatment for 24 h resulted in decreased protein levels of importin-α. These results suggest that ETAS prevents pro-inflammatory responses by suppressing the p65 nuclear translocation in skin fibroblasts induced by H2O2.

Enzyme-Treated Asparagus Extract Attenuates Hydrogen Peroxide-Induced Matrix Metalloproteinase-9 Expression in Murine Skin Fibroblast L929 Cells

Enzyme-treated asparagus extract (ETAS) exerts a wide variety of beneficial biological actions including facilitating anti-cortisol stress and neurological anti-aging responses. However, the anti-skin aging effects of ETAS remain to be elucidated. Reactive oxygen species (ROS) play pivotal roles in skin aging. Increased ROS levels in fibroblasts in response to ultraviolet irradiation activate c-Jun N-terminal kinase (JNK) and its downstream transcription factor activator protein-1 (AP-1), and the resultant gene expression of matrix metalloproteinase (MMP) isoforms accelerates collagen breakdown in the dermis. Therefore, we explored whether ETAS has anti-skin aging effects by attenuating the oxidative stress responses in fibroblasts. Simultaneous treatment of murine skin L929 fibroblasts with hydrogen peroxide (H2O2) and either ETAS or dextrin showed that ETAS significantly suppressed H2O2-induced expression of MMP-9 mRNA as measured by real-time polymerase chain reaction. ETAS also clearly suppressed H2O2-stimulated phosphorylation of c-Jun (AP-1 subunit) and JNK as determined by Western blot. However, ETAS did not affect the increased amounts of carbonyl proteins in response to H2O2, also as determined by Western blotting. These results suggest that ETAS diminishes cellular responsiveness to ROS but does not scavenge ROS. Thus, ETAS has the potential to prevent skin aging through attenuating the oxidative stress responses in dermal fibroblasts.