Active Hexose Correlated Compound (AHCC) is an extract of Lentinula edodes of the basidiomycete family of fungi rich in alpha glucans. AHCC has been used for many years as a dietary supplement to enhance the immune system and in clinical trials as an adjunctive treatment in Hepatocellular cancer. This multiple dose, Phase I trial, using FDA guidelines, directly investigates the clinical safety and tolerability of AHCC in healthy subjects. Its safety has been based previously on anecdotal reports and its use in clinical practice. Twenty-six healthy male or female subjects between the ages of 18 and 61 were recruited from the community and gave their consent to participate in the trial. The subjects were given 9 g of AHCC (150 mL of the currently available liquid AHCC) PO daily for 14 d. Laboratory data was obtained at baseline and after 14 d of exposure to AHCC and adverse events were monitored by a non-directed review of systems questionnaire three times during the trial. At each visit the vital signs and adverse events were recorded. Two subjects (7%) dropped out because of nausea and intolerance of the liquid. Adverse effects of nausea, diarrhea, bloating, headache, fatigue, and foot cramps occurred in a total of 6 subjects (20%) but were mild and transient. There were no laboratory abnormalities. When used in high dose in healthy subjects, AHCC causes no significant abnormality in laboratory parameters. The adverse effects of 9 g of liquid AHCC per day, a higher dose than used in routine clinical applications, are minimal and the dose was tolerated by 85% of the subjects.
Abstract Photosystem II (PSII) catalyses the oxidation of water through a four-step cycle of S i states ( i = 0–4) at the Mn 4 CaO 5 cluster 1–3 , during which an extra oxygen (O6) is incorporated at the S 3 state to form a possible dioxygen 4–7 . Structural changes of the metal cluster and its environment during the S-state transitions have been studied on the microsecond timescale. Here we use pump-probe serial femtosecond crystallography to reveal the structural dynamics of PSII from nanoseconds to milliseconds after illumination with one flash (1F) or two flashes (2F). Y Z , a tyrosine residue that connects the reaction centre P680 and the Mn 4 CaO 5 cluster, showed structural changes on a nanosecond timescale, as did its surrounding amino acid residues and water molecules, reflecting the fast transfer of electrons and protons after flash illumination. Notably, one water molecule emerged in the vicinity of Glu189 of the D1 subunit of PSII (D1-E189), and was bound to the Ca 2+ ion on a sub-microsecond timescale after 2F illumination. This water molecule disappeared later with the concomitant increase of O6, suggesting that it is the origin of O6. We also observed concerted movements of water molecules in the O1, O4 and Cl-1 channels and their surrounding amino acid residues to complete the sequence of electron transfer, proton release and substrate water delivery. These results provide crucial insights into the structural dynamics of PSII during S-state transitions as well as O–O bond formation.
Plant polyphenols with antioxidant and anti-inflammatory properties are effective in chemoprotection and chemoprevention. Oligonol is a novel formulation enriched with low molecular weight catechin-type oligomeric polyphenols. Administration of oligonol-L and oligonol-G, derived, respectively, from lychee fruit and grape seeds, by gavage significantly attenuated UVB-induced expression of COX-2 in hairless mouse skin. Intragastric administration of oligonol-L attenuated UVB-induced phosphorylation of extracellular signal-regulated protein kinase-1/2 and p38 mitogen-activated protein kinase in UVB-irradiated mouse skin. UVB irradiation induced phosphorylation of mitogen- and stress-activated kinase-1 (Msk1), Janus-activated kinase-2 (JAK2) and signal transducer and activator of transcription-3 (STAT3) in mouse skin. Pretreatment with oligonol-L diminished UVB-induced phosphorylation of Msk1, JAK2 and STAT3 in UVB-irradiated mouse skin. Furthermore, oligonol-L significantly induced the expression of NAD(P)H:quinone oxidoreductase-1 (NQO-1) in mouse skin. In summary, oligonol-L inhibited UVB-induced expression of COX-2 and various upstream kinases, and induced the expression of NQO-1, which may account for its protective effects against photoinjury, including photoageing and photocarcinogenesis.
Natural products or active components with a protective effect against oxidative stress have attracted significant attention for prevention and treatment of degenerative disease. Oligonol is a low molecular weight polyphenol containing catechin-type monomers and oligomers derived from Litchi chinensis Sonn. We investigated the protective effect and its related mechanism of oligonol against oxidative stress.Oxidative stress in C6 glial cells was induced by hydrogen peroxide (H2O2) and the protective effects of oligonol on cell viability, nitric oxide (NO) and reactive oxygen species (ROS) synthesis, and mRNA expression related to oxidative stress were determined.Treatment with oligonol inhibited NO and ROS formation under cellular oxidative stress in C6 glial cells. In addition, it recovered cell viability in a dose dependent-manner. Treatment with oligonol also resulted in down-regulated mRNA expression related to oxidative stress, nuclear factor kappa-B (NF-κB) p65, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS), compared with the control group treated with H2O2. In particular, expression of NF-κB p65, COX-2, and iNOS was effectively reduced to the normal level by treatment with 10 µg/mL and 25 µg/mL of oligonol.These results indicate that oligonol has protective activity against oxidative stress-induced inflammation. Oligonol might be a promising agent for treatment of degenerative diseases through inhibition of ROS formation and NF-κB pathway gene expression.
How information encoded in glutamate release rates at individual synapses is converted into biochemical activation patterns of postsynaptic enzymes remains unexplored. To address this, we developed a dual fluorescence resonance energy transfer (FRET) imaging platform and recorded CaMKIIα and calcineurin activities in hippocampal neurons while varying glutamate uncaging frequencies. With little spine morphological change, 5 Hz spine glutamate uncaging strongly stimulated calcineurin, but not CaMKIIα. In contrast, 20 Hz spine glutamate uncaging, which induced spine growth, activated both CaMKIIα and calcineurin with distinct spatiotemporal kinetics. Higher temporal resolution recording in the soma revealed that CaMKIIα activity summed supralinearly and sensed both higher frequency and input number, thus acting as an input frequency/number decoder. In contrast, calcineurin activity summated sublinearly with increasing input number and showed little frequency dependence, thus functioning as an input number counter. These results provide evidence that CaMKIIα and calcineurin are fine-tuned to unique bandwidths and compute input variables in an asymmetric manner.