Effect of a traditional Japanese herbal medicine, hochu-ekki-to (Bu-Zhong-Yi-Qi Tang), on immunity in elderly persons

Use of anti-aging herbal medicine, Lycium barbarum, against aging-associated diseases. What do we know so far?

Lycium barbarum (Gouqizi, Fructus Lycii, Wolfberry) is well known for nourishing the liver, and in turn, improving the eyesight. However, many people have forgotten its anti-aging properties. Valuable components of L. barbarum are not limited to its colored components containing zeaxanthin and carotene, but include the polysaccharides and small molecules such as betaine, cerebroside, beta-sitosterol, p-coumaric, and various vitamins. Despite the fact that L. barbarum has been used for centuries, its beneficial effects to our bodies have not been comprehensively studied with modern technology to unravel its therapeutic effects at the biochemical level. Recently, our laboratory has demonstrated its neuroprotective effects to counter neuronal loss in neurodegenerative diseases. Polysaccharides extracted from L. barbarum can protect neurons against beta-amyloid peptide toxicity in neuronal cell cultures, and retinal ganglion cells in an experimental model of glaucoma. We have even isolated the active component of polysaccharide which can attenuate stress kinases and pro-apoptotic signaling pathways. We have accumulated scientific evidence for its anti-aging effects that should be highlighted for modern preventive medicine. This review is to provide background information and a new direction of study for the anti-aging properties of L. barbarum. We hope that new findings for L. barbarum will pave a new avenue for the use of Chinese medicine in modern evidence-based medicine.

Hochu-ekki-to inhibits rhinovirus infection in human tracheal epithelial cells

BACKGROUND AND PURPOSE

A traditional Japanese herbal medicine, hochu-ekki-to, has been used for the symptomatic treatment of the common cold and to reduce the frequency of colds in patients with chronic obstructive pulmonary disease. However, the inhibitory effects of hochu-ekki-to on infection by rhinovirus (RV), the major cause of common colds, have not been studied.

EXPERIMENTAL APPROACH

Human tracheal epithelial cells in culture were infected with a major group rhinovirus-RV14. Virus output and viral RNA were measured along with interleukin (IL)-1beta, IL-6, IL-8 and tumor necrosis factor (TNF)-alpha), mRNA for intercellular adhesion molecule (ICAM)-1 and acidic endosomes in cells.

KEY RESULTS

RV14 infection increased virus titers, the content of cytokines in supernatants and RV14 RNA in the cells. Hochu-ekki-to decreased virus output, RV14 RNA in the cells, susceptibility to RV infection and supernatant cytokine concentrations after RV14 infection. Hochu-ekki-to reduced mRNA for ICAM-1, the receptor for RV14, the concentration of the soluble form of ICAM-1 and the number and fluorescence intensity of acidic endosomes in the cells, from which RV RNA enters into the cytoplasm, at RV14 infection. Glycyrrhizin, one of the chemical constituents of hochu-ekki-to, reduced supernatant virus titers dose-dependently.

CONCLUSION AND IMPLICATIONS

Hochu-ekki-to inhibited RV14 infection by decreasing ICAM-1 and by blocking entry of viral RNA into the cytoplasm from the endosomes, in airway epithelial cells. Glycyrrhizin may be partly responsible for inhibition of RV infection by hochu-ekki-to. Hochu-ekki-to could modulate airway inflammation by reducing production of cytokines in RV infections.

No effect of a traditional Chinese medicine, Hochu-ekki-to, on antibody titer after influenza vaccination in man: a randomized, placebo-controlled, double-blind trial

BACKGROUND

It was shown that a traditional Chinese medicine, Hochu-ekki-to (HET), had adjuvant effects in influenza vaccination in an animal experiment. This, however, could not be assessed in a clinical study.

METHODS

Thirty-two healthy subjects were randomly assigned to two groups (control and HET groups) in a double-blind manner. HET subjects (n=17) took 7.5 g of HET/day for two weeks; control subjects took the same amount of indistinguishable placebo. Then subjects were vaccinated against influenza (H1N1, H3N2 and B/Shandong). Hemagglutinin titers and natural killer (NK) activity were measured at weeks 0, 1, 2, 4, and 12.

RESULTS

Antiinfluenza titers against the three viruses were increased continuously for the first two weeks and leveled off. However, there were no significant differences in any titers between the two groups. NK activity peaked at week 2 without any inter-group differences.

CONCLUSION

We could not find any adjuvant effects of HET in this experimental condition.