Dihydroisocoumarins of Hydrangea macrophylla var. thunbergia inhibit binding of the SARS-CoV-2 spike protein to ACE2.

Binding of the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to the cognate angiotensin-converting enzyme 2 (ACE2) receptor is the initial step in the viral infection process. In this study, we screened an in-house extract library to identify food materials with inhibitory activity against this binding using enzyme-linked immunosorbent assays and attempted to ascertain their active constituents. Hydrangea macrophylla var. thunbergia leaves were identified as candidate materials. Its active compounds were purified using conventional chromatographic methods and identified as naringenin, dihydroisocoumarins, hydrangenol, and phyllodulcin, which have affinities for the ACE2 receptor and inhibit ACE2 receptor-spike S1 binding. Given that boiled water extracts of H. macrophylla leaves are commonly consumed as sweet tea in Japan, we speculated that this tea could be used as a potential natural resource to reduce the risk of SARS-CoV-2 infection.

Golden berry leaf extract containing withanolides suppresses TNF-α and IL-17 induced IL-6 expression in HeLa Cells.

Inflammation, characterized by the overexpression of IL-6 in various tissues, has been reported as a symptom of coronavirus disease 2019. In this study, we established an experimental system for overexpression of IL-6 in HeLa cells stimulated by TNF-α and IL-17, along with identification of anti-inflammatory materials and components from local agricultural, forestry, and fishery resources. We constructed a library of extracts from natural sources, of which 111 samples were evaluated for their anti-inflammatory activities. The MeOH extract of Golden Berry (Physalis peruviana L) leaf was found to exhibit strong anti-inflammatory properties (IC50 = 4.97 µg/mL). Preparative chromatography identified two active constituents, 4ß-hydroxywithanolide E (4ß-HWE) (IC50 = 183 nM) and withanolide E (WE) (IC50 = 65.1 nM). Withanolides are known anti-inflammatory ingredients of Withania somnifera, an Ayurvedic herbal medicine. P. peruviana leaves containing 4ß-HWE and WE should be considered as useful natural resources for anti-inflammatory products.

Anti-melanogenic effect of furanoeremophilanes identified from edible wild plants belonging to the genus Cacalia.

Cacalia delphiniifolia and Cacalia hastata are edible wild plants in Japan. We found that these plants have anti-melanogenic activity in B16F10 mouse melanoma cells. Three furanoeremophilanes, cacalol (from C. delphiniifolia), dehydrocacalohastin, and cacalohastin (from C. hastata), were identified as the main active components. The genus Cacalia may be a good source of beneficial materials with anti-melanogenic effects.

A yeast-based screening system identified bakkenolide B contained in Petasites japonicus as an inhibitor of interleukin-2 production in a human T cell line.

Ca2+ signaling is related to various diseases such as allergies, diabetes, and cancer. We explored Ca2+ signaling inhibitors in natural resources using a yeast-based screening method and found bakkenolide B from the flower buds of edible wild plant, Petasites japonicus, using the YNS17 strain (zds1Δ erg3Δ pdr1/3Δ). Bakkenolide B exhibited growth-restoring activity against the YNS17 strain and induced Li+ sensitivity of wild-type yeast cells, suggesting that it inhibits the calcineurin pathway. Additionally, bakkenolide B inhibited interleukin-2 production at gene and protein levels in Jurkat cells, a human T cell line, but not the in vitro phosphatase activity of human recombinant calcineurin, an upstream regulator of interleukin-2 production. Furthermore, bakkenolide A showed weak activity in YNS17 and Jurkat cells compared with bakkenolide B. These findings revealed new biological effects and the structure-activity relationships of bakkenolides contained in P. japonicus as inhibitors of interleukin-2 production in human T cells.

Associations of streptococci and fungi amounts in the oral cavity with nutritional and oral health status in institutionalized elders: a cross sectional study.

BACKGROUND: Disruption of the indigenous microbiota is likely related to frailty caused by undernutrition. However, the relationship between undernutrition and the oral microbiota, especially normal bacteria, is not obvious. The aim of this study was to elucidate the associations of nutritional and oral health conditions with prevalence of bacteria and fungi in the oral cavity of older individuals. METHODS: Forty-one institutionalized older individuals with an average age ± standard deviation of 84.6 ± 8.3 years were enrolled as participants. Body mass index (BMI) and oral health assessment tool (OHAT) scores were used to represent nutritional and oral health status. Amounts of total bacteria, streptococci, and fungi in oral specimens collected from the tongue dorsum were determined by quantitative polymerase chain reaction (PCR) assay results. This study followed the STROBE statement for reports of observational studies. RESULTS: There was a significant correlation between BMI and streptococcal amount (ρ = 0.526, p < 0.001). The undernutrition group (BMI < 20) showed a significantly lower average number of oral streptococci (p = 0.003). In logistic regression models, streptococcal amount was a significant variable accounting for "not undernutrition" [odds ratio 5.68, 95% confidential interval (CI) 1.64-19.7 (p = 0.06)]. On the other hand, participants with a poor oral health condition (OHAT ≥ 5) harbored significantly higher levels of fungi (p = 0.028). CONCLUSION: Oral streptococci were found to be associated with systemic nutritional condition and oral fungi with oral health condition. Thus, in order to understand the relationship of frailty with the oral microbiota in older individuals, it is necessary to examine oral indigenous bacteria as well as etiological microorganisms.

The effect of eating sea cucumber jelly on Candida load in the oral cavity of elderly individuals in a nursing home.

We conducted a double-blind randomized controlled study of elderly individuals in a nursing home to investigate the effect of the consumption of jelly containing sea cucumber on their oral Candida load. The jelly contained a hydrolysate of the sea cucumber Stichopus japonicus, which contained triterpene glycosides called holotoxins. The holotoxins worked as a fungicide, and their minimum inhibitory concentrations for Candida albicans were 7 µg/mL. Eight individuals in the nursing home took the sea cucumber jelly for a week and their oral Candida were counted before and after the intervention. Nine individuals took a control jelly without S. japonicus. The sea cucumber jelly showed inhibitory effects on the oral Candida. Thus, daily consumption of the S. japonicus jelly has the potential to reduce the oral Candida load in the elderly in nursing homes.

Sequential chiral induction between organic and inorganic supramolecular helical assemblies for the in situ formation of chiral carbon dots.

Self-organised helical bilayers of dicationic gemini surfactants confined in helical silica nanospace were transformed in situ to carbon dots (CDots) via pyrolysis. These water-dispersible CDots exhibit electronic absorption spanning the UV and visible range and possess symmetrical circular dichroism (CD) signals, the sign of which depends on the handedness of the helices.

Beneficial effects by intake of Euphausiacea pacifica on high-fat diet-induced obesity.

Obesity is a major health problem showing increased incidence in developed and developing countries. We examined the effect of Euphausia pacifica (E. pacifica) (Pacific Krill) on high-fat diet (HFD)-induced obesity in C57BL/6 mice. No significant differences were observed in average food intake between the HFD and HFD with E. pacifica group, or the low-fat diet (LFD) and LFD with E. pacifica group for 18 weeks. The increased ratio of body weight in the HFD containing E. pacifica group was significantly reduced, being 10% lower than that with HFD group in the 18th week (HFD, 298.6±18.8% vs. HFD with E. pacifica, 267.8±16.2%; p<0.05), while the ratio for the LFD containing E. pacifica group was reduced by 4% compared with LFD group (LFD, 244.2±11.6% vs. LFD with E. pacifica, 234.1±18.0%). There were no effects of E. pacifica on total cholesterol levels in serum and liver, whereas the supplement of E. pacifica tended to decrease triglyceride levels in the HFD groups. The leptin level in serum was significantly decreased in the HFD group (p<0.01) by E. pacifica. The adipocyte area (1926±1275 µm(2)) in the HFD containing E. pacifica group was significantly reduced by 20% (p<0.001) compared with the HFD group. These results suggested that E. pacifica supplementation in the diet is beneficial for the prevention of HFD-induced obesity.

Inhibitory effects of polysaccharides on the cariogenic activities of Streptococcus mutans.

Many carbohydrates are involved in the biofilm formation and activities of glucosyltransferases (Gtfs) of Streptococcus mutans, and the effects of various disaccharides and polysaccharides were investigated in this study, including the hot water-extracted glucan fraction of the Lentinula edodes fruiting body (HWG). HWG was found to inhibit the initial adhesion of S. mutans to saliva-coated hydroxyapatite (sHA), and also laminarin to inhibit glucan synthesis by Gtfs. However, sucrose-dependent biofilm formation by S. mutans was not inhibited by these materials. Interestingly, dextran was found to have an inhibitory effect on the sucrose-dependent biofilm formation. The data suggest that the presence of such an edible glucan as dextran in daily foods would act to some degree on S. mutans for suppressing the cariogenic activity.

Petasin is the main component responsible for the anti-adipogenic effect of Petasites japonicus.

Petasites japonicus is one of the most popular edible wild plants in Japan. Many biological effects of P. japonicus have been reported, including anti-allergy, anti-inflammation, and anticancer effects. Although its anti-obesity effect has been reported in several studies, the most important component responsible for this activity has not been fully elucidated. On screening the components that suppress adipocyte differentiation in 3T3-F442A cells, we found that the extract of the flower buds of P. japonicus has anti-adipogenic effect. Among the known major components of P. japonicus, petasin exhibited a potent anti-adipogenic effect at an IC50 value of 0.95 µM. Quantitative analysis revealed that the active component responsible for most of the anti-adipogenic effects of P. japonicus extract is petasin. Petasin suppressed the expression of markers of mature adipocytes (PPARγ, C/EBPα, and aP2). However, as isopetasin and petasol, analogs of petasin, did not exhibit these effects, it indicates that a double bond at the C11-C12 position and an angeloyl ester moiety were essential for the activity. Petasin affected the late stage of adipocyte differentiation and inhibited the expression of lipid synthesis factors (ACC1, FAS, and SCD1). Additionally, it was revealed that petasin could be efficiently extracted using hexane with minimal amount of pyrrolizidine alkaloids, the toxic components. These findings indicate that P. japonicus extract containing petasin could be a promising food material for the prevention of obesity.

Controllable spectrum artificial sunlight source system using LEDs with 32 different peak wavelengths of 385-910 nm.

This study developed a lighting system that produces an approximate spectral irradiance (SI) of ground level sunlight in the wavelength range of 385-910 nm (GLS385₋910) using 547 light-emitting diodes (LEDs) with 32 different peak wavelengths. The produced SI can be modified over an arbitrary wavelength band. The SI at the light outlet reached up to 1/2 of the GLS385₋910 of a sunny April day, although the produced SI deviated from the GLS385₋910 at some wavelengths. For subsequent experiments, the reference SI was defined as 1/4 GLS385₋910 of a sunny April day. The SI produced from the lighting system was adjusted to approximate the reference SI. The ratios of the produced SI and the reference SI were within 0.72-1.28. As an application of the lighting system for biological studies, the transmitted SI of a green leaf of perilla (Perilla frutescens L.) was investigated. The curve shape of the transmitted SI, which had characteristically low transmission percentages of blue and red light, reflected the characteristics of the absorption spectra of chlorophylls. The lighting system is therefore potentially beneficial for use in diagnosing physiological conditions of plant leaves, although its application is not limited to plant physiological studies.

Production of indole from L-tryptophan and effects of these compounds on biofilm formation by Fusobacterium nucleatum ATCC 25586.

The l-tryptophan degradation product indole is a purported extracellular signaling molecule that influences biofilm formation in various bacteria. Here we analyzed the mechanisms of indole production in Fusobacterium nucleatum and the effects of tryptophan and indole on F. nucleatum planktonic and biofilm cells. The amino acid sequence deduced from the fn1943 gene in F. nucleatum ATCC 25586 was 28% identical to that deduced from tnaA in Escherichia coli, which encodes tryptophanase catalyzing the beta-elimination of l-tryptophan to produce indole. The fn1943 gene was cotranscribed with the downstream gene fn1944, which is a homolog of tnaB encoding low-affinity tryptophan permease. The transcript started at position -68 or -153 from the first nucleotide of the fn1943 translation initiation codon. Real-time quantitative PCR showed that much more F. nucleatum fn1943 transcripts were obtained from log-phase cells than from stationary-phase cells. Indole production by the purified recombinant protein encoded by fn1943 was examined using high-performance liquid chromatography. The K(m) and k(cat) of the enzyme were 0.26 +/- 0.03 mM and 0.74 +/- 0.04 s(-1), respectively. F. nucleatum biofilm formation and the biofilm supernatant concentration of indole increased dose dependently with increasing tryptophan concentrations. Exogenous indole also increased F. nucleatum biofilm formation in a dose-dependent manner. Even at very high concentrations, tryptophan did not affect fn1943 expression, whereas similar indole concentrations decreased expression. Thus, exogenous tryptophan and indole were suggested to increase F. nucleatum biofilms.

The inhibitory effects of mushroom extracts on sucrose-dependent oral biofilm formation.

Mushrooms contain large quantities of alpha-glucans. Shiitake (Lentinula edodes), Japan's most popular edible mushroom, has been reported to contain about 6% (weight/dried weight) of alpha-(1,3)-glucan. This glucan is one of the major components of oral biofilm formed by the cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus. We found that extracts from shiitake and other edible mushrooms could reduce preformed biofilms of S. mutans and S. sobrinus in the presence of dextranase. We also investigated the alpha-glucanase activities of shiitake mushroom extracts and their effects on biofilm formation. The extracts possessed alpha-glucanase activity and degraded water-insoluble glucans from mutans streptococci. The extracts strongly inhibited the sucrose-dependent formation of biofilms by S. mutans and S. sobrinus in the presence of dextranase. Our results suggest that some components of mushrooms, including alpha-glucanases, might inhibit the sucrose-induced formation of oral biofilms.

Identification of a novel enzyme from E. pacifica that acts as an eicosapentaenoic 8R-LOX and docosahexaenoic 10R-LOX.

North Pacific krill (Euphausia pacifica) contain 8R-hydroxy-eicosapentaenoic acid (8R-HEPE), 8R-hydroxy-eicosatetraenoic acid (8R-HETE) and 10R-hydroxy-docosahexaenoic acid (10R-HDHA). These findings indicate that E. pacifica must possess an R type lipoxygenase, although no such enzyme has been identified in krill. We analyzed E. pacifica cDNA sequence using next generation sequencing and identified two lipoxygenase genes (PK-LOX1 and 2). PK-LOX1 and PK-LOX2 encode proteins of 691 and 686 amino acids, respectively. Recombinant PK-LOX1 was generated in Sf9 cells using a baculovirus expression system. PK-LOX1 metabolizes eicosapentaenoic acid (EPA) to 8R-HEPE, arachidonic acid (ARA) to 8R-HETE and docosahexaenoic acid (DHA) to 10R-HDHA. Moreover, PK-LOX1 had higher activity for EPA than ARA and DHA. In addition, PK-LOX1 also metabolizes 17S-HDHA to 10R,17S-dihydroxy-docosahexaenoic acid (10R,17S-DiHDHA). PK-LOX1 is a novel lipoxygenase that acts as an 8R-lipoxygenase for EPA and 10R-lipoxygenase for DHA and 17S-HDHA. Our findings show PK-LOX1 facilitates the enzymatic production of hydroxy fatty acids, which are of value to the healthcare sector.

Total light approach of time-domain fluorescence diffuse optical tomography.

In this study, time-domain fluorescence diffuse optical tomography in biological tissue is numerically investigated using a total light approach. Total light is a summation of excitation light and zero-lifetime emission light divided by quantum yield. The zero-lifetime emission light is an emitted fluorescence light calculated by assuming that the fluorescence lifetime is zero. The zero-lifetime emission light is calculated by deconvolving the actually measured emission light with a lifetime function, an exponential function for fluorescence decay. The object for numerical simulation is a 2-D 10 mm-radius circle with the optical properties simulating biological tissues for near infrared light, and contains regions with fluorophore. The inverse problem of fluorescence diffuse optical tomography is solved using time-resolved simulated measurement data of the excitation and total lights for reconstructing the bsorption coefficient and fluorophore concentration simultaneously. The mean time of flight is used as the featured data-type extracted from the time-resolved data. The reconstructed images of fluorophore concentration show good quantitativeness and spatial reproducibility. By use of the total light approach, computation is performed much faster than the conventional ones.

[Neuroendocrine carcinoma of the prostate effectively treated by cisplatin and irinotecan--a case report].

A 79-year-old man was referred to our hospital with urinary retention in August 2004. Because the serum PSA was 2,9 39 ng/mL,we performed transabdominal prostatic needle biopsy. Pathological examination of the prostate revealed conventional adenocarcinoma. CT scans and MRI showed a huge mass and lymph node metastasis. He was treated with diethyl stilbestrol diphosphate,followed by maximal androgen blockade therapy,and the serum PSA level decreased favorably. Follow-up CT revealed prostate and lymph node metastasis were reduced, but liver metastases, measuring 45 x 34 mm and 28 x 24 mm, respectively, were newly recognized in February 2006. The NSE level was high at 88.5 ng/mL, so a percutaneous liver biopsy was performed,and pathological examination of the liver revealed metastatic prostate cancer which showed neuroendocrine differentiation. The treatment was changed to chemotherapy comprising cisplatin and irinotecan. After three courses of the chemotherapy,liver metastasis was reduced in CT scans.

Nrf2 Activation by 5-lipoxygenase Metabolites in Human Umbilical Vascular Endothelial Cells.

5-hydroxyeicosatetraenoic acid (5-HETE) and 5-hydroxyeicosapentaenoic acid (5-HEPE) are major metabolites produced by 5-lipoxygenase (5-LOX) from arachidonic acid (AA) and eicosapentaenoic acid (EPA). Effects of hydroxides on endothelial cells are unclear, although 5-LOX is known to increase at arteriosclerotic lesions. To investigate the effects of hydroxides on human umbilical vein endothelial cells (HUVECs), the cells were treated with 50 µM each of AA, EPA, 5-HETE, and 5-HEPE. Treatment of HUVECs with 5-HETE and 5-HEPE, rather than with AA and EPA, increased the nuclear translocation of NF-E2 related factor 2 (Nrf2) and upregulated the expression of heme oxygenase-1 and cystine/glutamate transporter regulated by Nrf2. Reactive oxygen species (ROS) generation was markedly elevated in HUVECs after treatment with 5-HETE and 5-HEPE, and the pretreatment with α-tocopherol abrogated ROS levels similar to those in the vehicle control. However, ROS generation was independent of Nrf2 activation induced by 5-HETE and 5-HEPE. 5-HETE was converted to 5-oxo-eicosatetraenoic acid (5-oxo-ETE) in HUVECs, and 5-oxo-ETE increased Nrf2 activation. These results suggest that 5-HETE works as an Nrf2 activator through the metabolite 5-oxo-ETE in HUVECs. Similarly, 5-HEPE works in the same way, because 5-HEPE is metabolized to 5-oxo-eicosapentaenoic acid through the same pathway as that for 5-HETE.

Lipids, fatty acids and hydroxy-fatty acids of Euphausia pacifica.

Euphausia pacifica is a good candidate for a resource of marine n-3 PUFA. However, few reports exist of the lipid and fatty acid composition of E. pacifica. To examine the potential of E. pacifica as a resource of marine n-3 PUFA, we analyzed E. pacifica oil. We extracted lipids from E. pacifica harvested from the Pacific Ocean near Sanriku, Japan. Lipid classes of E. pacifica oil were analyzed by TLC-FID and the fatty acid composition of the oil was analyzed by GC/MS. Free fatty acids and hydroxy-fatty acids were analyzed by LC/QTOFMS. The lipid content of E. pacifica ranged from 1.30% to 3.57%. The ratios of triacylglycerols, phosphatidylcholine, phosphatidylethanolamine and free fatty acids in E. pacifica lipids were 5.3-23.0%, 32.6-53.4%, 8.5-25.4% and 2.5-7.0%, respectively. The content of n-3 PUFA in E. pacifica lipids was 38.6-46.5%. We also showed that E. pacifica contains unusual fatty acids and derivatives: C16-PUFAs (9,12-hexadecadienoic acid, 6,9,12-hexadecatrienoic acid and 6,9,12,15-hexadecatetraenoic acid) and hydroxy-PUFAs (8-HETE and 10-HDoHE). E. pacifica is a good resource of marine n-3 PUFA. Moreover, E. pacifica can provide C16-PUFA and hydroxy-PUFAs.

Production of Fab fragment corresponding to surface protein antigen of Streptococcus mutans serotype c-derived peptide by Escherichia coli and cultured tobacco cells.

The cDNA of a mouse Fab fragment was cloned from a hybridoma cell line that produces a mouse monoclonal antibody, KH5, that reacts with the peptide fragment of the surface protein antigen of Streptococcus mutans serotype c (PAc). After transfection with cDNA, recombinant Fab fragments were produced by Escherichia coli (T15 Fab) and cultured tobacco cells (X253 and X262 Fabs). The antipeptide activities of T15 and X253 were similar to that of KH5. X253 was secreted into the culture media, which had a specific affinity for the PAc peptide.

The short term feasibility of abdominoperineal resection with prostatectomy for locally advanced rectal cancer: open and laparoscopic cases report.

Total pelvic exenteration is often selected for advanced rectal cancer with prostatic invasion. The aim of this study was to evaluate the short term feasibility of the abdominoperineal resection with prostatectomy for locally advanced rectal cancer. We performed abdominoperineal resection with prostatectomy for 3 patients with locally advanced rectal cancer, including 2 patients by totally laparoscopic procedure. Patients' background, intra- and postoperative factors and short-term prognosis were evaluated. All patients underwent complete resection of primary tumor with negative surgical margins. We could perform the surgery by both open and laparoscopic procedure in collaboration with urologist. There was no operation related mortality. One patient who was treated by open procedure had urinary anastomotic leakage. No patient had recurrenced, but one patient died of other disease. Our experience suggests that open or laparoscopic abdominoperineal resection with prostatectomy could be an alternative to total pelvic exenteration for the patients with rectal cancer invading the prostate. The collaboration with the urologist would be important to perform quality-controlled surgery.