The inhibitory effect of oral administration of lentinan on DSS-induced inflammation is exerted by the migration of T cells activated in the ileum to the colon.

Oral administration of lentinan ameliorated dextran sulfate sodium (DSS)-induced colitis through Dectin-1 receptor on intestinal epithelial cells. However, it is unclear where lentinan affects in the intestine to prevent the inflammation. We found that the administration of lentinan has induced migration of CD4+ cells from the ileum to the colon by using Kikume Green-Red (KikGR) mice in this study. This result suggests that the oral lentinan treatment could accelerate the migration of Th cells in lymphocyte from ileum into the colon during lentinan intake. Then, C57BL/6 mice were administered 2% DSS to induce colitis. The mice were administered lentinan daily via oral or rectal route before DSS administration. Its rectal administration also suppressed DSS-induced colitis, but its suppressive effects were lower compared to when orally administered, indicating that the biological responses to lentinan in the small intestine contributed to the anti-inflammatory effects. In normal mice (without DSS treatment), the expression of Il12b was significantly increased in the ileum by the oral administration of lentinan, but not by rectal one. On the other hand, no change was observed in the colon by either administration method. In addition, Tbx21 was significantly increased in the ileum. These suggested that IL-12 was increased in the ileum and Th1 cells differentiated in dependence on it. Therefore, Th1 predominant condition in the ileum could influence immunity in the colon and improve the colitis.

Not a fungi to be with: Shiitake mushroom flagellate dermatitis.

Shiitake dermatitis is a rare adverse cutaneous reaction to the ingestion of raw or undercooked shiitake mushrooms (Lentinula edodes). We report the case of a patient who developed a striking linear flagellate dermatitis without urticaria three days after returning from a trip from Tokyo where he had eaten shiitake mushrooms. The rash resolved after two weeks with topical corticosteroids and antihistamines given for symptomatic relief. Shiitake dermatitis is thought to be either a toxic or hypersensitivity reaction to lentinan, a heat-inactivated polysaccharide found in the cell walls of shiitake mushrooms. Although this mushroom is widely consumed in Eastern Asia, with the increasing globalisation of cuisine and travel, cases are likely to become more common in the Western world.

[Reflectance confocal microscopy in Shiitake dermatitis]. / Konfokale Lasermikroskopie bei Shiitake-Dermatitis.

Shiitake dermatitis usually occurs 1-2 days after consumption of incompletely cooked or raw shiitake mushrooms and is characterized by linear, pruritic, erythematous papulovesicular rashes. It is caused by lentinan, a polysaccharide component of the cell walls of shiitake mushrooms. The histological examination showed an eczema-like morphology with spongiosis and lymphohistiocytic infiltrates. The results of reflectance confocal microscopy (RCM) correlated with the histopathological investigations. Therefore, RCM can be used for non-invasive diagnostic confirmation of Shiitake dermatitis in the future.

Mushroom polysaccharide lentinan for treating different types of cancers: A review of 12 years clinical studies in China.

Lentinula edodes has been used to improve general health for thousands of years in Asia. It is the second largest cultivated and the most popular edible mushroom in the world known as "Xianggu" in China and "Shiitake" in Japan. Lentinan is a polysaccharide extracted from Lentinula edodes. ß-Glucan is the major bioactive component in lentinan with immunostimulatory effect. The antitumor property of lentinan was reported in 1960s. Biochemical studies indicate that immunocytes can be activated by lentinan through multiple signaling pathways, such as TLR4/Dectin1-MAPK and Syk-PKC-NFκB pathways. Though it has been approved as an adjuvant therapeutic drug both in China and Japan for treating cancers since 1980s, a systematic review of clinical studies of lentinan has not been conducted elaborately. In this review, over 9474 reported lentinan-associated cancer treatment cases are evaluated and summarized from 135 independent studies in China during the past 12 years (2004-2016) based on CNKI (China National Knowledge Infrastructure), VIP (Chongqing VIP Chinese Scientific Journals Database) and Wanfang database. The 9474 reported lentinan-associated cancer treatment cases include lung cancer (3469 cases), gastric cancer (3039 cases), colorectal cancer (1646 cases), ovarian cancer (183 cases), cervical cancer (130 cases), Non-Hodgkin lymphoma (70 cases), pancreatic cancer (15 cases), cardiac cancer (15 cases), nasopharyngeal cancer (14 cases), duodenal cancer (1 case) and 110 cancer cases with no classifying patient information. Overall clinical data show solid effect of lentinan on improving the quality of life and on promoting the efficacy of chemotherapy and radiation therapy during cancer treatment.

Shiitake Mushroom Dermatitis: A Review.

Shiitake mushroom dermatitis is a cutaneous reaction caused by the consumption of raw or undercooked shiitake mushrooms. Symptoms include linear erythematous eruptions with papules, papulovesicles or plaques, and severe pruritus. It is likely caused by lentinan, a heat-inactivated beta-glucan polysaccharide. Cases were initially reported in Japan but have now been documented in other Asian countries, North America, South America, and Europe, as this mushroom is now cultivated and consumed worldwide. Shiitake mushroom dermatitis may result from mushroom ingestion or from handling, which can result in an allergic contact dermatitis.

Flagellate shiitake mushroom dermatitis.

An 84-year-old woman presented with 5 days of a pruritic skin eruption that formed arciform and linear patterns. She was diagnosed with flagellate shiitake mushroom dermatitis related to shiitake mushroom consumption the day prior symptom onset.

The effect of lentinan combination therapy for unresectable advanced gastric cancer.

BACKGROUND: Developed as a biological response modifier (BRM), lentinan mitigates patients' symptoms by boosting the immune system. In combination with S-1 (tegafur, gimeracil, oteracil), lentinan is reported to mitigate adverse reactions to therapy for unresectable recurrent gastric cancer and prolong survival. However, there are few reports from actual clinical practice, and precise methods of using lentinan have not yet been established. This study retrospectively examined the usefulness of lentinan in patients. PATIENTS AND METHODS: The subjects of this study were 39 patients who were diagnosed with unresectable gastric cancer, based on preoperative examinations or findings at laparotomy in our Department. These patients underwent S-1/paclitaxel therapy. Nineteen of the patients received lentinan while 20 did not, and these two groups of patients were compared. RESULTS: There were no significant differences in patients' characteristics such as the male:female ratio, age at the start of chemotherapy, and staging classification of the 19 patients receiving lentinan and the 20 patients not receiving lentinan. Comparison of the two groups revealed no significant differences in overall survival time, but comparison of the duration of therapy revealed that therapy tended to be longer for the group taking lentinan than the group not taking lentinan. Adverse events were noted in 61.5% (24 patients) of the total patients group; such events tended to occur less frequently in the group receiving lentinan. CONCLUSION: Lentinan inclusion in therapy did not seem to prolong survival. Nevertheless, the duration of therapy tended to be longer for patients taking lentinan. This may be due to the fact that adverse events tended to occur less frequently in these patients during therapy. A decline in the incidence of adverse events increases the duration of therapy and improves the patients' quality of life (QOL); it may also prolong survival. Optimal methods of using lentinan need to be established.

Supplementation with a soluble ß-glucan exported from Shiitake medicinal mushroom, Lentinus edodes (Berk.) singer mycelium: a crossover, placebo-controlled study in healthy elderly.

Lentinus edodes (Shiitake) is a medicinal mushroom with a long tradition of use in Asia. The major active substance in L. edodes is a (1-6,1-3)-beta-glucan (lentinan). No clinical controlled studies have yet investigated the effect of orally administered lentinan on the immune response in healthy, elderly Caucasian subjects. We evaluated the effect and the safety of a beta-glucan from L. edodes mycelium, Lentinex, in healthy, elderly subjects in a double blind, crossover, placebo-controlled trial. Forty-two subjects were randomly allocated to two groups given orally either 2.5 mg/day Lentinex or placebo for 6 weeks; then after a washout period of 4 weeks, the alternate supplementation was given for 6 weeks. The changes in the number of B-cells were significantly different between the groups. The number ofNK cells increased significantly in both groups, but there was no significant difference between the groups. Other factors of the immune response (immunoglobulins, complement proteins, cytokines) were not altered. The safety blood variables (differential cell count, liver function, kidney function, and other blood chemistry) were not influenced by Lentinex, and the number, nature, and severity of adverse events were similar to placebo. Lentinex given orally to elderly subjects was safe and induced an increase in the number of circulating B-cells.

[Combination chemotherapy of S-1/low-dose CDDP/lentinan for advanced gastric cancer].

Eight patients with inoperable advanced gastric cancer were treated with combination chemotherapy of S-1, low-dose cisplatin(CDDP)and Lentinan. S-1 80 mg/ m² was orally administered for 2 weeks followed by 1-week rest, CDDP 15 mg/ m² and Lentinan 2 mg/body were given intravenously on day 1 and 8. One complete response and four partial responses were observed for an overall response rate of 63%(5 of 8 patients). Only one patient developed over grade 3 toxicity leukocytopenia. Many patients could be maintained by long-term continuous treatment. Since combination chemotherapy of S-1/low-dose CDDP/Lentinan for advanced gastric cancer was very tolerable, it could be used for a long time.

[Shiitake dermatitis now occurs in France]. / La shiitake dermatitis (dermatose toxique au lentin) est arrivée en France.

BACKGROUND: In Asia, toxic adverse effects due to picking or consumption of shiitake mushrooms (Lentinula edodes), the second most eaten mushroom in the world are well-known. Its increasing consumption in Europe, let us to emphasize that shiitake dermatitis would occur more and more frequently in Occident. CASE REPORT: A 78-year-old woman was referred for an erythematous, micro-papular, extremely pruriginous rash disseminated all over the body (including face and scalp). No drugs had been recently introduced. Questioning revealed that lesions appeared 48 hours after eating a great quantity of raw shiitake mushrooms, leading to the diagnosis of shiitake dermatitis. DISCUSSION: Clinical features of shiitake dermatitis are small, highly pruriginous, erythematous papules, generalized. They have a whole body spreading and in some area a linear disposition. It is a toxic reaction due to a toxin called lentinan. It occurs in the 48 hours after having eaten raw or slightly cooked mushrooms and vanishes into 10 days. Due to its increasing consumption in Occident, it is essential for European dermatologists to know this dermatosis and how to recognize it.

Efficacy of orally administered superfine dispersed lentinan (beta-1,3-glucan) for the treatment of advanced colorectal cancer.

BACKGROUND: Lentinan (LNT) is an immune adjuvant medicine for advanced gastric cancer in Japan. Recently, an oral formulation of superfine dispersed lentinan (SDL) has become clinically available. To investigate the safety and effectiveness of SDL, a multi center clinical study in patients with advanced colorectal cancer was conducted. PATIENTS AND METHODS: Adverse events were assessed and the patients' quality of life (QOL) and the binding ability of peripheral blood monocytes (PBM) to LNT were also evaluated. RESULTS: Four grade 2 adverse events associated with SDL treatment were observed among the 80 patients. Adverse events associated with chemotherapy were observed in 9 out of the 64 chemotherapy-treated patients. Among the 48 patients assessed for QOL, the patients with low QOL scores before SDL treatment (n=23) reported a significant improvement in their QOL scores after 12 weeks of SDL administration. The rates of LNT-binding PBM in the QOL-improved group were significantly higher than those in the QOL-not-improved group (p<0.05). CONCLUSION: SDL was safe and effective for suppressing the adverse effects of chemotherapy as well as improving QOL. The binding ability of PBM to LNT appears to be a promising predictor of QOL improvement after SDL administration.