A systematic review and meta-analysis of efficacy and safety of compound glycyrrhizin combined with second-generation non-sedated antihistamine for the treatment of chronic urticaria

BACKGROUND

Chronic urticaria (CU) is a prevalent dermatologic disease that negatively affects life, current therapies remain suboptimal. Hence, there is an urgent need to identify effective and safe treatment.

OBJECTIVE

Assess the efficacy and safety of compound glycyrrhizin (CG) combined with second-generation nonsedated antihistamine for the treatment of CU.

METHODS

Nine databases were queried to screen RCTs related. Two reviewers independently assessed the risk of bias using Cochrane Collaboration. Primary objective was the total efficiency rate, while secondary was rate of recurrence, adverse events, and cure. Statistical analyses using Review Manager 5.4 and Stata17.

RESULTS

Twenty-four RCTs were identified. Significant differences were noted in rate of total efficiency (n = 2649, RR = 1.36, 95%CI:1.30-1.43, p < 0.00001), cure (n = 2649, RR = 1.54, 95%CI:1.42-1.66, p < 0.00001) and recurrence (n = 446, RR = 0.34, 95%CI:0.20-0.58, p < 0.00001) between the combination of CG with second-generation non-sedated antihistamine and antihistamine monotherapy. Contrastingly, adverse events rate (n = 2317, RR = 0.76, 95% CI:0.59-0.97, p = 0.03) was comparable between the two groups. Our results indicated that CG combined with second-generation non-sedated antihistamine could significantly mitigate the symptoms in CU compared with antihistamine monotherapy. No serious adverse events were reported.

CONCLUSIONS

CG combined with second-generation nonsedated antihistamine is effective for CU. Nevertheless, higher-quality studies are warranted to validate our results.

Colon-targeted piperine-glycyrrhizic acid nanocrystals for ulcerative colitis synergetic therapy via macrophage polarization

Ulcerative colitis (UC) is a chronic inflammatory disease that affects the gastrointestinal tract and is characterized by immune dysregulation. Oral administration of nanoformulations containing immunomodulators is a desirable approach to treating UC. However, low drug-loading (<10%, typically), premature drug release, and systemic absorption of these nanoformulations continue to be significant challenges restricting clinical applications. Herein, we developed colon-targeted piperine-glycyrrhizic acid nanocrystals (ES100-PIP/GA NCs) to treat UC through the regulation of macrophages. The ES100-PIP/GA NCs exhibited ultra-high drug loading and colon-specific drug release. In vitro studies demonstrated that the ES100-PIP/GA NCs could effectively be internalized by lipopolysaccharide (LPS)-induced RAW 264.7 and Caco-2 cells. More importantly, the ES100-PIP/GA NCs could downregulate pro-inflammatory factors (IL-1β, IL-17A), upregulate anti-inflammatory factors (TGF-β1), and repair the intestinal mucosal barrier. In a murine model of acute colitis induced by dextran sodium sulfate (DSS), ES100-PIP/GA NCs could protect PIP and GA from gastric acid destruction, reach the colon, and significantly inhibit colitis. Surprisingly, ES100-PIP/GA NCs enhance M2 macrophages by increasing the mammalian target of rapamycin (mTOR), and inhibit M1 macrophages by reducing hypoxia-inducible factor-1α (HIF-1α). Overall, this study shows that ES100-PIP/GA NCs have synergistic immunotherapy capabilities with macrophage regulation, which offers a promising blueprint for the oral delivery of multicomponent drugs in UC therapy.

Blockade of HMGB1 Reduces Inflammation and Pruritus in Atopic Dermatitis by Inhibiting Skin Fibroblasts Activation

INTRODUCTION

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by relapsed eczema and serious pruritus. High-mobility group box 1 protein (HMGB1) is a nuclear-binding protein and serves as an alarmin to promote inflammatory responses.

METHODS

In this study, we established an AD mouse model by topical use of MC903 on ears and then used a specific HMGB1-binding peptide cIY8 and a HMGB1 inhibitor of glycyrrhizin to investigate HMGB1 on fibroblast activation in the pathogenesis of AD-like symptoms.

RESULTS

Topical use of cIY8 and oral use of glycyrrhizin significantly improved the MC903-induced AD-like symptoms and pathological changes of the ears and scratching behavior in an AD mouse model; cIY8 treatment inhibited the higher mRNAs of IL-1α, IL-4, IL-5, IL-13, and IL-31 in the ears. In human fibroblasts, HMGB1 caused nuclear translocation of NF-kB, and the nuclear translocation could be inhibited by pre-treatment of HMGB1 with cIY8, suggesting that NF-κB signaling pathway participates in the HMGB1-induced inflammation of AD in fibroblasts and that cIY8 effectively impedes the function of HMGB1. Glycyrrhizin inhibited the Ca2+ signaling induced by ionomycin in mouse primary fibroblasts. The fibroblast-related proteins of α-SMA, Hsp47, and vimentin and the pruritus-related proteins of IL-33 and periostin were increased in the ears of the AD mouse model, the ratio of EdU incorporation became higher in mouse fibroblasts treated with MC903, and the higher proliferation and inflammatory responses of the fibroblasts could be reversed by glycyrrhizin treatment.

CONCLUSIONS

Fibroblast activation by HMGB1 is one of the critical processes in the development of inflammation and pruritus in the AD mouse model. The specific HMGB1-binding peptide cIY8 and the HMGB1 inhibitor glycyrrhizin inactivate skin fibroblasts to alleviate the inflammation and pruritus in the AD mouse model. Peptide cIY8 may be topically used to treat AD patients in the future.

[Adverse effects of licorice consumed as food: An update]

The word "licorice" refers to the plant, its root, and its aromatic extract. From a commercial point of view, Glycyrrhiza glabra is the most important species with a wide range of uses (herbal medicine, tobacco industry, cosmetics, food and pharmaceutical). Glycyrrhizin is one of the main constituents of licorice. Glycyrrhizin is hydrolyzed in the intestinal lumen by bacterial β-glucuronidases to 3β-monoglucuronyl-18β-glycyrrhetinic acid (3MGA) and 18β-glycyrrhetinic acid (GA), which are metabolized in the liver. Plasma clearance is slow due to enterohepatic cycling. 3MGA and GA can bind to mineralocorticoid receptors with very low affinity, and 3MGA induces apparent mineralocorticoid excess syndrome through dose-dependent inhibition of 11β-hydroxysteroid dehydrogenase type 2 in renal tissue. The cases of apparent mineralocorticoid excess syndrome reported in the literature are numerous and sometimes severe, even fatal, most often in cases of chronic high dose consumption. Glycyrrhizin poisonings are characterized by hypertension, fluid retention, and hypokalemia with metabolic alkalosis and increased kaliuresis. Toxicity depends on the dose, the type of product consumed, the mode of consumption (acute or chronic) and a very large inter-individual variability. The diagnosis of glycyrrhizin-induced apparent mineralocorticoid excess syndrome is based on the history, clinical examination, and biochemical analysis. Management is primarily based on symptomatic care and stopping licorice consumption.

Glycyrrhizin ameliorates impaired glucose metabolism and ovarian dysfunction in a polycystic ovary syndrome mouse model

The aim of this study was to determine the impact of glycyrrhizin, an inhibitor of high mobility group box 1, on glucose metabolic disorders and ovarian dysfunction in mice with polycystic ovary syndrome. We generated a polycystic ovary syndrome mouse model by using dehydroepiandrosterone plus high-fat diet. Glycyrrhizin (100 mg/kg) was intraperitoneally injected into the polycystic ovary syndrome mice and the effects on body weight, glucose tolerance, insulin sensitivity, estrous cycle, hormone profiles, ovarian pathology, glucolipid metabolism, and some molecular mechanisms were investigated. Increased number of cystic follicles, hormonal disorders, impaired glucose tolerance, and decreased insulin sensitivity in the polycystic ovary syndrome mice were reverted by glycyrrhizin. The increased high mobility group box 1 levels in the serum and ovarian tissues of the polycystic ovary syndrome mice were also reduced by glycyrrhizin. Furthermore, increased expressions of toll-like receptor 9, myeloid differentiation factor 88, and nuclear factor kappa B as well as reduced expressions of insulin receptor, phosphorylated protein kinase B, and glucose transporter type 4 were restored by glycyrrhizin in the polycystic ovary syndrome mice. Glycyrrhizin could suppress the polycystic ovary syndrome-induced upregulation of high mobility group box 1, several inflammatory marker genes, and the toll-like receptor 9/myeloid differentiation factor 88/nuclear factor kappa B pathways, while inhibiting the insulin receptor/phosphorylated protein kinase B/glucose transporter type 4 pathways. Hence, glycyrrhizin is a promising therapeutic agent against polycystic ovary syndrome.

Efficacy of diammonium glycyrrhizinate in the treatment of rosacea with papules and pustules: A randomized, double-blind, placebo-controlled study

Rosacea is a kind of chronic inflammatory skin disease that usually occurs in the middle of the face. Diammonium glycyrrhizinate (DG), an effective monomer component extracted from licorice, has extensive anti-inflammatory, antioxidant, anti-allergic, and immunomodulatory effects. There is no research on its therapeutic effect on rosacea. In this study, we divided rosacea patients mainly characterized by papules and pustules randomly into three groups. Group A received clarithromycin 500 mg once a day, isotretinoin 10 mg once a day; Group B received DG 150 mg three times a day, other medicines were the same as Group A; Group C received clarithromycin 250 mg once a day, isotretinoin 10 mg once every 2 days, and DG 150 mg three times a day. All patients' symptom scores and laboratory tests were evaluated when followed up. We found that DG combined with clarithromycin and isotretinoin in the treatment of rosacea was more effective and quicker than clarithromycin and isotretinoin alone. Moreover, half common dosage of clarithromycin and isotretinoin combined with DG could achieve the same therapeutic effect as the conventional dose, and brought about lower incidences of adverse events (AEs). Therefore, it is recommended to use half common dosage of routine medication combined with DG for rosacea patients mainly characterized by papules and pustules.

Desloratadine citrate combined with compound glycyrrhizin in the treatment of subacute eczema: A randomized trial

To investigate the efficacy of desloratadine citrate combined with compound glycyrrhizin in the treatment of subacute eczema. 100 patients with subacute eczema who were admitted in our hospital from June 2019 to June 2020 were selected according to the order of admission, and divided into experimental groups (n=50, using a single compound glycyrrhizin) and control group (n=50, using compound glycyrrhizin combined with desloratadine citrate); the curative effect was compared between the two groups. After treatment, the inflammatory factors in the experimental group were lower than those in the control group [TNF-α (ng/L) (35.16±3.31), IL-2 (pg/ml) (24.39±3.11), IL-4 (pg/ml) (39.82± 4.48) vs TNF-α (ng/L) (44.24±3.87), IL-2 (pg/ml) (41.68±3.89), IL-4 (pg/ml) (49.88±5.74)] (P<0.05). After treatment the adverse reaction rate of the experimental group was lower than that of the control group (P<0.05). After treatment,the experimental group yielded higher total effective rate in relative to the control group (P<0.05). Desloratadine citrate plus compound glycyrrhizinfor might be a preferable option for clinical treatment of patients with subacute eczema, with an ideal effectiveness profile.

Glycyrrhizin-Induced Pseudohyperaldosteronism: A Case Report

In conclusion, this case should remind clinicians of the potential dangers of glycyrrhizin (high blood pressure, low blood potassium and abnormal changes in ECG, among other effects). The timely detection and effective treatment of glycyrrhizin-induced PsHA can prevent the occurrence of serious complications. The importance of taking a detailed medical history is also emphasized.

Compound glycyrrhizin combined with antihistamines for chronic urticaria: A protocol for systematic review and meta analysis

BACKGROUND

To investigate the efficacy and safety of compound glycyrrhizin (CG) combined with antihistamines in the treatment of chronic urticaria (CU).

METHODS

We will use computers to search all databases including Medline, Embase, Pubmed, Web of Science and Cochrane Central Register of Controlled Trials and China's 4 databases: China National Knowledge Infrastructure Database, China Biomedical Literature Database, China Science Journal Database, and Wanfang Database. Find data from creation date to July 2020. In addition, we will manually search the list of medical journals as a supplement. The scope of the search included randomized controlled clinical studies related to CG combined with antihistamines for CU. The primary outcome is the disease activity control. Secondary outcomes include response rate, adverse events, and recurrence rates. The Cochrane RevMan V5.3 Deviation Assessment Tool will be used to assess bias assessment risk, data integration risk, meta-analysis risk, and subgroup analysis risk (if conditions are met). The average difference, standard mean difference, and binary data will be used to represent continuous results.

RESULTS

This study will comprehensively review the existing evidence on CG combined with antihistamines for CU.

CONCLUSION

This systematic review will provide a basis for judging the effectiveness and safety of CG combined with antihistamines in the treatment of CU.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42020156153.

Hypertensive crisis with 2 target organ impairment induced by glycyrrhizin: A case report

RATIONALE

Glycyrrhizin is the main active component of licorice. Licorice and glycyrrhizin induced hypertension has been widely reported, yet licorice and glycyrrhizin induced hypertensive crisis has been rarely known.

PATIENT CONCERNS

The case of this report was a 47-year-old woman, who took 225 mg of glycyrrhizin daily for 3 years due to primary biliary cholangitis. She was found to have a dramatically elevated blood pressure of about 230/110 mmHg without a history of hypertension and was referred to the emergency department.

DIAGNOSES

Hypokalemia, hypertensive retinopathy, and nephropathy were found during the following work-up. Since no other risk factors of hypertension were identified, she was suspected to have glycyrrhizin induced pseudo-hyperaldosteronism.

INTERVENTIONS

Glycyrrhizin was discontinued. Intravenous sodium nitroprusside was used during the first few days. Nifedipine and irbesartan were taken after discharge, and the dosage was reduced gradually under supervision.

OUTCOMES

She stopped all the anti-hypertensive drugs 6 months since glycyrrhizin was stopped. Her blood pressure was about 110/60 mmHg after repetitive measurement. Her serum potassium and urine albumin/creatinine ratio were also normalized.

LESSONS

Licorice and glycyrrhizin induced hypertension due to pseudo-hyperaldosteronism has been widely reported, yet only 3 cases reported that excessive consumption of licorice could lead to hypertensive emergencies. This is the first case that glycyrrhizin induced hypertensive crisis with target organ impairment. By presenting this case, we remind clinicians of glycyrrhizin induced hypertension, a condition which could lead to medical emergencies.

The association between consistent licorice ingestion, hypertension and hypokalaemia: a systematic review and meta-analysis

There have been numerous case reports of severe adverse events including deaths following chronic licorice ingestion. The aim of the present study was to evaluate the effect of chronic ingestion of licorice on blood pressure, plasma potassium, plasma renin activity and plasma aldosterone. A search of MEDLINE, PubMed, EMBASE, CENTRAL, DARE, CINAHL and Current Contents Connect was performed from inception through to 26 April 2017. Trials that included a treatment group ingesting a product containing at least 100 mg of glycyrrhizic acid daily were selected. Pooled mean changes from baseline with 95% confidence intervals were calculated for diastolic blood pressure, systolic blood pressure, plasma potassium, plasma renin activity and plasma aldosterone using a random effects model. An assessment of dose-response was also undertaken. A total of 18 studies (n=337) were included in the meta-analysis. There was a statistically significant increase in mean systolic blood pressure (5.45 mm Hg, 95% CI 3.51-7.39) and diastolic blood pressure (3.19 mm Hg, 95% CI 0.10-6.29) after chronic ingestion of a product containing glycyrrhizic acid. Plasma potassium (-0.33 mmol l-1, 95% CI -0.42 to 0.23), plasma renin activity (-0.82 ngml-1 per hour, 95% CI -1.27 to -0.37) and plasma aldosterone (-173.24 pmol l-1, 95% CI -231.65 to -114.83) were all significantly decreased. A significant correlation was noted between daily dose of glycyrrhizic acid and systolic blood pressure (r2=0.55) and diastolic blood pressure (r2=0.65), but not for the other outcome measures. Hence, chronic licorice ingestion is associated with an increase in blood pressure and a drop in plasma potassium, even at modest doses. This is of particular relevance for individuals with existing cardiovascular disease.

Maternal Licorice Consumption During Pregnancy and Pubertal, Cognitive, and Psychiatric Outcomes in Children

Earlier puberty, especially in girls, is associated with physical and mental disorders. Prenatal glucocorticoid exposure influences the timing of puberty in animal models, but the human relevance of those findings is unknown. We studied whether voluntary consumption of licorice, which contains glycyrrhizin (a potent inhibitor of placental 11β-hydroxysteroid dehydrogenase type 2, the "barrier" to maternal glucocorticoids), by pregnant women was associated with pubertal maturation (height, weight, body mass index for age, difference between current and expected adult height, Tanner staging, score on the Pubertal Development Scale), neuroendocrine function (diurnal salivary cortisol, dexamethasone suppression), cognition (neuropsychological tests), and psychiatric problems (as measured by the Child Behavior Checklist) in their offspring. The children were born in 1998 in Helsinki, Finland, and examined during 2009-2011 (mean age = 12.5 (standard deviation (SD), 0.4) years; n = 378). Girls exposed to high maternal glycyrrhizin consumption (≥500 mg/week) were taller (mean difference (MD) = 0.4 SD, 95% confidence interval (CI): 0.1, 0.8), were heavier (MD = 0.6 SD, 95% CI: 0.2, 1.9), and had higher body mass index for age (MD = 0.6 SD, 95% CI: 0.2, 0.9). They were also 0.5 standard deviations (95% CI: 0.2, 0.8) closer to adult height and reported more advanced pubertal development (P < 0.04). Girls and boys exposed to high maternal glycyrrhizin consumption scored 7 (95% CI: 3.1, 11.2) points lower on tests of intelligence quotient, had poorer memory (P < 0.04), and had 3.3-fold (95% CI: 1.4, 7.7) higher odds of attention deficit/hyperactivity disorder problems compared with children whose mothers consumed little to no glycyrrhizin (≤249 mg/week). No differences in cortisol levels were found. Licorice consumption during pregnancy may be associated with harm for the developing offspring.

Compound glycyrrhizin plus conventional therapy for psoriasis vulgaris: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Psoriasis vulgaris is a chronic skin condition affecting patients' quality of life. Long-term use of conventional therapy increases risk of unwanted side effects. Compound glycyrrhizin in conjunction with conventional therapy has been used in clinical practice, but the evidence for such practice has not been evaluated systematically.

OBJECTIVE

This review aims to evaluate the efficacy and safety of compound glycyrrhizin in combination with conventional therapy for psoriasis vulgaris.

METHODS

PubMed, Excerpta Medica dataBASE (Embase), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Central Register of Controlled Trials, Allied and Complementary Medicine Database (AMED), CiNii, Chinese Biomedical Literature, China National Knowledge Infrastructure, Chinese Scientific Journals Full Text Database and Wanfang Data were searched from their respective inceptions to July 2015. Randomized controlled trials comparing compound glycyrrhizin plus conventional therapy to conventional therapy alone for psoriasis vulgaris were included. Data analysis was performed using Review Manager 5.3.

RESULTS

Eleven randomized controlled trials were included in this review. Meta-analysis of the 11 randomized controlled trials indicated that the addition of compound glycyrrhizin increased the number of patients achieving Psoriasis Area and Severity Index (PASI) 60 (RR: 1.30 [1.21, 1.40], I² = 6%), when compared with conventional therapy alone. Comparable numbers of patients experienced adverse events in the two groups.

CONCLUSIONS

Compound glycyrrhizin in conjunction with conventional therapy enhances clinical response, and compound glycyrrhizin as add-on therapy does not appear to pose any additional risk in the treatment of psoriasis vulgaris. However, the findings should be interpreted with caution of methodological flaws in the included studies. PROSPERO registration number: CRD42015027763.

Efficacy and safety of a medical device in reducing nasal obstruction in allergic children

AIM

Despite the availability of a number of pharmacological options, relief of allergic rhinitis (AR) symptoms, especially nasal obstruction, is often limited and local and systemic adverse reactions are not infrequent. The main aim of the present pilot study was to provide subjective and objective evidence of the clinical efficacy in reducing symptoms and safety of a medical device-Grip stop DMG (lactoferrin, carboximetil β-glucan, D-panthenol, dipotassiumglycyrrhizinate) in children affected by allergic rhinitis.

METHODS

A prospective study with a pre- and post-design has been performed consecutively enrolling 50 pediatric both genders patients affected by persistent AR. Patients received 2 puffs into each nostril twice a day over the course of 4 weeks. The severity of AR symptoms was assessed subjectively as measured by a 0 to 5 Visual Analog Scale, and objectively through active anterior rhinomanometry (AAR) and by means of the evaluation of mucociliary transport time (MCTt). Differences in symptoms scores measured before and after the treatment were compared using Paired-Sample Wilcoxon Signed Rank Test. Proportion of participants with adverse effects attributed to the treatment was computed. The relationship between the subjective score and the AAR and MCT measurements was also assessed.

RESULTS

All considered symptoms, including nasal congestion, significantly improved after treatment (P<0.001), while only 1 patient suffered from moderate adverse effects.

CONCLUSION

Results confirm efficacy and safety of this device used in the pediatric population. As previously reported in the scientific literature, also in our study, patient's perception of nasal symptoms corresponded with objective testing.

A semi-physiologically based pharmacokinetic pharmacodynamic model for glycyrrhizin-induced pseudoaldosteronism and prediction of the dose limit causing hypokalemia in a virtual elderly population

Glycyrrhizin (GL) is a widely used food additive which can cause severe pseudoaldosteronism at high doses or after a long period of consumption. The aim of the present study was to develop a physiologically based pharmacokinetic (PBPK) pharmacodynamic (PD) model for GL-induced pseudoaldosteronism to improve the safe use of GL. Since the major metabolite of GL, glycyrrhetic acid (GA), is largely responsible for pseudoaldosteronism via inhibition of the kidney enzyme 11β-hydroxysteroiddehydrogenase 2 (11β-HSD 2), a semi-PBPK model was first developed in rat to predict the systemic pharmacokinetics of and the kidney exposure to GA. A human PBPK model was then developed using parameters either from the rat model or from in vitro studies in combination with essential scaling factors. Kidney exposure to GA was further linked to an Imax model in the 11β-HSD 2 module of the PD model to predict the urinary excretion of cortisol and cortisone. Subsequently, activation of the mineralocorticoid receptor in the renin-angiotensin-aldosterone-electrolyte system was associated with an increased cortisol level. Experimental data for various scenarios were used to optimize and validate the model which was finally able to predict the plasma levels of angiotensin II, aldosterone, potassium and sodium. The Monte Carlo method was applied to predict the probability distribution of the individual dose limits of GL causing pseudoaldosteronism in the elderly according to the distribution of sensitivity factors using serum potassium as an indicator. The critical value of the dose limit was found to be 101 mg with a probability of 3.07%.

Antiviral effects of the constituents derived from Chinese herb medicines on infectious bursal disease virus

CONTEXT

The prevalence of infectious bursal disease has brought about enormous financial losses to the world poultry industry. Chinese herb medicines can provide valuable materials for discovery and development of new drugs.

OBJECTIVE

To screen constituents derived from Chinese herb medicines for their antiviral activity against infectious bursal disease virus (IBDV) in vitro.

MATERIALS AND METHODS

Twenty constituents derived from Chinese herb medicines and B87 strain of IBDV were used. The 50% cytotoxic concentration (CC₅₀) and 50% effective concentration (EC₅₀) were determined by visualization of cytopathologic effect (CPE) and 3-(4,5-dimethyithiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) test on chicken embryo fibroblast. Selectivity index (SI) and inhibition ratio (%I) were calculated from the data obtained from the MTT test.

RESULTS

Antiviral assays showed dipotassium glycyrrhizinate and ligustrazine hydrochloride among the 20 constituents tested exhibited significant inhibitory activity against IBDV in a dose-dependent manner. EC₅₀ of dipotassium glycyrrhizinate and ligustrazine hydrochloride were 663.2 ± 268.4 and 92.52 ± 21.13 µg/mL, and SI were >4.52 and >21.62, respectively. The time-of-addition and virucidal assay indicated that anti-IBDV activity of the two constituents could be due to their inhibiting virus replication and/or inactivating virus directly. The inhibition of virus attachment was not observed in the adsorption inhibition assay. Dipotassium glycyrrhizinate and ligustrazine hydrochloride exhibited more than 70% and 80% inhibition of IBDV, respectively, at the maximum safe concentration.

DISCUSSION AND CONCLUSION

We believe that dipotassium glycyrrhizinate and ligustrazine hydrochloride can be used to develop a new anti-IBDV compound, and it is worth applying the constituents in clinical practice.

Efficacy of glycyrrhizin combined with cyclosporine in the treatment of non-severe aplastic anemia

BACKGROUND

Cyclosporine A (CsA) has been widely used in the treatment of aplastic anemia (AA), but the application of CsA was limited in patients who had liver diseases or abnormal liver function due to its liver toxicity. Glycyrrhizin has long been used in China in the treatment of various liver diseases to lower transaminases. In this study, we observed the efficacy and safety of glycyrrhizic acid combined with CsA in the treatment of newly diagnosed patients with non-severe AA (NSAA).

METHODS

A total number of 76 patients with newly diagnosed NSAA were enrolled into the study at our hospital between July 2005 and June 2010. The patients were divided randomly into two groups: the glycyrrhizin-treatment group (group A) and the control group (group B) with 38 patients in each group. All patients received 3 - 5 mg×kg(-1)×d(-1) CsA for at least 4 months and were treated either with or without glycyrrhizin for 4 months.

RESULTS

sixty-eight patients were eligible for evaluation. In the control group, 9.09% patients (n = 3) achieved a complete response while 51.52% (n = 17) attained a partial response. The overall response rate was 60.61% (n = 20). The remaining 13 patients (39.39%) did not have any response. In the glycyrrhizin-treatment group, complete response rate was 20% (n = 7) and partial response rate was 62.86% (n = 22). The overall response rate was 82.86% (n = 29) and the non-response rate was 17.14% (n = 6). Response rate was significantly increased with the addition of glycyrrhizin to CsA compared with CsA alone (P < 0.05).

CONCLUSION

The combination of glycyrrhizin and cyclosporine regimen was an effective treatment for NSAA in terms of improvement of response rate, reduction in CsA-related liver injury, and attenuation of severity of nausea and other adverse events in the treatment of patients with NSAA.

Early determinants of mental health

Environmental adversities in pre- and early postnatal life may have life-long consequences. Based upon a series of epidemiological and clinical studies and natural experiments, this review describes how the early life environment may affect psychological functions and mental disorders later in life. We focus on studies that have examined the associations of small body size at birth and prematurity as proxies of prenatal environmental adversity. We also review literature on materno-fetal malnutrition, maternal prenatal glycyrrhizin in licorice consumption and hypertension-spectrum pregnancy disorders as factors that may compromise the fetal developmental milieu and hence provide insight into some of the mechanisms that may underlie prenatal programming. While effects of programming mostly take place during the first 1000 days after conception, we finally present evidence from prospective studies suggesting that programming can occur also during later critical periods of development or 'windows of plasticity'. The studies may bear relevance for future prevention and intervention programs targeting the potentially modifiable environmental factors that will aid at promoting mental well-being and health of an individual.

Pseudoaldosteronism with increased serum cortisol associated with pneumonia, hypouricemia, hypocalcemia, and hypophosphatemia

We describe here the interesting case of a 73-year-old hypertensive man with pseudoaldosteronism. He had been taking glycyrrhizin at a dose of 75 mg/day for 12 years because of mild liver damage, but had never experienced any previous symptoms associated with hypokalemia. He was referred to our hospital because of hypokalemic tetraparesis and rhabdomyolysis. At that time, we noted mineralocorticoid excess characterized by hypokalemia due to urinary K loss, exacerbation of hypertension due to increased tubular Na reabsorption, metabolic alkalosis, and suppression of both plasma renin activity and plasma aldosterone concentration. His urinary free cortisol excretion rate and the urinary ratio of free cortisol to free cortisone were markedly elevated. Thus we diagnosed pseudoaldosteronism that was related to the long-term use of glycyrrhizin. When he developed pseudoaldosteronism, he also contracted pneumonia, and exhibited elevated levels of serum cortisol and creatinine clearance (CCr) as well as hypouricemia, hypocalcemia, and hypophosphatemia. All normalized after the recovery from pneumonia and the administration of spironolactone. The extracellular volume expansion associated with increased tubular Na reabsorption by the aldosterone-sensitive distal nephron and the resulting increase in CCr caused an inhibition of proximal tubular reabsorption of uric acid, Ca, and inorganic phosphate, leading to their renal loss and therefore hypouricemia, hypocalcemia, and hypophosphatemia, respectively. In this patient, the increased circulating cortisol associated with the stress of inflammation caused by pneumonia triggered the development of pseudoaldosteronism.

Is glycyrrhizin sensitivity increased in anorexia nervosa and should licorice be avoided? Case report and review of the literature

OBJECTIVE

Hypokalemia is a potentially life-threatening electrolyte disturbance in anorexia nervosa and is most frequently caused by purging behavior. We report a case of severe hypokalemia in anorexia nervosa induced by daily ingestion of approximately 20 g of licorice.

METHODS

To confirm the diagnosis of licorice-induced pseudohyperaldosteronism, a re-exposure trial was performed.

RESULTS

Cessation of the licorice intake normalized plasma potassium, renin, and aldosterone levels and the urine cortisol/cortisone ratio. Re-exposure confirmed the diagnosis. The pronounced response to a relatively low daily dose of licorice suggests high glycyrrhizin sensitivity.

CONCLUSION

Patients with anorexia nervosa not only have decreased food intake but also selective and sometimes bizarre eating habits that, in association with increased sensitivity to glycyrrhizin, may cause severe hypokalemia.

[Clinical characteristics of five elderly patients with severe hypokalemia induced by glycyrrhizin derivatives]

Although hypokalemia is a common clinical problem, symptoms generally do not become manifest unless the serum potassium (K) falls rapidly. We encountered five cases with symptomatic severe hypokalemia (K<2.0 mEq/L) hospitalized for the past 15 months at our hospital. We examined the clinical characteristics and treatment of these patients. All five patients were women, and their mean age was 77.8 (73-82)years. They suffered from hypertension. Mean K level at admission was 1.66 (1.4-1.9) mEq/L and HCO3(-) was 48.3 (33.6-56.1) mmol/L. Plasma aldosterone level was low and plasma rennin activity was suppressed. All patients developed progressive muscle weakness with elevated creatinine phosphokinase. Three of the patients had received Chinese medicine which contained licorice, one received glycyrrhizin and the other one had received both. We diagnosed these cases as pseudoaldosteronism induced by glycyrrhizin. With discontinuation of the drugs and intravenous as well as oral K supplementation, serum K were normalized and clinical symptoms improved within 12 days. For one patient who developed cardiac dysfunction, concentrated K solution (230 mEq/L) was infused into the central vein. These findings show that glycyrrhizin ingestion should be kept in mind as a cause of an extreme degree of an hypokalemia, especially in elderly patients.

[Magnesium isoglycyrrhizinate in the treatment of chronic liver diseases: a randomized, double-blind, multi-doses, active drug controlled, multi-center study]

OBJECTIVE

To evaluate the efficacy and safety of Magnesium isoglycyrrhizinate in treatment of chronic liver diseases.

METHODS

It is a randomized, double-blind, multi-doses, active drug controlled, multi-center study. 480 proper patients were randomly divided into group A (180 patients), group B (180 patients) or group C (120 patients). Patients in group A received magnesium isoglycyrrhizinate 100 mg once daily. Patients in group B received magnesium isoglycyrrhizinate 150 mg once daily. Patients in group C received compound glycyrrhizin 120 mg once daily. The treatment course was 4 weeks. Patients were followed up 2 weeks after the treatment. Patients visited once every 2 weeks. Clinical symptoms, ALT, AST were evaluated in all the patients before treatment, at week 2, at week 4 and at 2 weeks later after treatment. The other liver function test was done before treatment and at week 4.

RESULTS

412 patients completed the study according to the protocol,152 in group A, 160 in group B and 100 in group C. ALT and AST level were significantly decreased in all groups at week 2 and week 4 (P < 0.05). The degree of ALT decrease is greater in group B than in group C at week 2 (P < 0.01). The degree of ALT decrease was not significant different among three groups at week 4 (P > 0.05). The rates of ALT improvement at week 4 in group A, B, C were 92.59%, 91.76%, 88.29%, respectively (P > 0.05). The rates of symptoms improvement at week 4 in group A, B, C were 90.41%, 89.86%, 86.46% and 72.22%, 73.53%, 68.47%, respectively (P > 0.05). No relapse were found in all three groups after treatment. The rate of adverse event in three groups was similar (P > 0.05).

CONCLUSION

Magnesium isoglycyrrhizinate is an effective and safe treatment for chronic liver diseases.

Pseudoaldosteronism caused by combined administration of cilostazol and glycyrrhizin

We report a case of obvious pseudoaldosteronism which occurred after the additional administration of cilostazol against arteriosclerosis obliterans (ASO) for bilateral legs in a 65 year-old man patient who had safely received glycyrrhizin for the previous ten years. Serum potassium level of the patient had been kept above 4 mEq/L until initiating cilostazol in November, 2006, then gradually decreased to 2.5 mEq/L for the following seven months. Both plasma renin activity and aldosterone were suppressed under co-administration of the angiotensin converting enzyme inhibitor, imidapril and the angiotensin II receptor blocker, olmesartan, both of which had been prescribed for longer than a year. Urinary potassium excretion was accelerated even in the critical level of hypokalemia. Because other drugs and supplements had not been changed at least for a year, pseudoaldosteronism caused by the combination of glycyrrhizin and another triggering factor, possibly cilostazol was highly suspected. By discontinuation of glycyrrhizin, potassium supplement, and the additional administration of the aldosterone blocker, spironolactone, the serum potassium level returned to the normal level two weeks later, even though cilostazol had been continued to avoid progression in his ASO. This is the first report of a case exhibiting pseudoaldosteronism induced by the interaction of glycyrrhizin with cilostazol, not by glycyrrhizin alone.

Effect of Compound Glycyrrhizin Injection on liver function and cellular immunity of children with infectious mononucleosis complicated liver impairment

OBJECTIVE

To investigate the effects of Compound Glycyrrhizin Injection (CGI) on liver function and cellular immunity of children with infectious mononucleosis complicated liver impairment (IM-LI) and to explore its clinical therapeutic effect.

METHODS

Forty-two patients with IM-LI were randomly assigned, according to the randomizing number table, to two groups, 20 in the control group and 22 in the treated group. All the patients were treated with conventional treatment, but to those in the treated group, CGI was given additionally once a day, at the dosage of 10 ml for children aged below 2 years, 20 ml for 2-4 years old, 30 ml for 5-7 years old and 40 ml for 8- 12 years old, in 100-200 ml of 5% glucose solution by intravenous dripping. The treatment lasted for 2 weeks. T lymphocyte subsets and serum levels of alanine transaminase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBil) were detected before and after treatment. Besides, a normal control group consisting of 20 healthy children was also set up.

RESULTS

Baseline of the percentage of CD3 + , CD8 + lymphocyte and serum levels of ALT, AST, TBiL in the children with IM-LI were markedly higher, while the percentage of CD4 + lymphocyte and the CD4 + /CD8 + ratio was markedly lower in IM-LI children as compared with the corresponding indices in the healthy children ( P<0.01). These indices were improved after treatment in both groups of patients, but the improvement in the treated group was better than that in the control group (P<0.01).

CONCLUSION

Cellular immunity dysfunction often occurs in patients with IM-LI, and CGI treatment can not only obviously promote the recovery of liver function, but also regulate the immune function in organism.

Biochemical and histological effects of 26 weeks of glycyrrhizin treatment in chronic hepatitis C: a randomized phase II trial

BACKGROUND/AIMS

Phase I/II studies of 4 weeks duration have confirmed the ALT lowering effect of glycyrrhizin in Western chronic hepatitis C patients. Our aim was to determine the dose frequency of glycyrrhizin required to maintain the ALT response beyond 4 weeks and evaluate its effect on liver histology and quality of life.

METHODS

HCV-RNA-positive patients with elevated ALT and marked fibrosis or necro-inflammation who were not eligible for interferon therapy were treated for 4 weeks with six infusions weekly of glycyrrhizin. Patients with an ALT response at week 4 were randomized to continue treatment for 22 weeks in three dose frequency groups: 6x, 3x or once weekly.

RESULTS

72/121 (60%) patients were randomized. At the end of treatment the ALT response was maintained in 60%, 24% and 9% of patients in the 6x, 3x, and once weekly groups, respectively (p<0.001). In ALT responders the necro-inflammation score improved non-significantly compared to ALT non-responders. Quality of life assessed by SF-36 increased in patients treated with the study drug, albeit unrelated to the occurrence of ALT response.

CONCLUSIONS

ALT responses induced by 4 weeks glycyrrhizin therapy can be maintained in a subset of chronic hepatitis C patients receiving at least three injections weekly. The observed ALT response did not translate in a significant histological improvement after 6 months treatment.

Pseudoaldosteronism due to the concurrent use of two herbal medicines containing glycyrrhizin: interaction of glycyrrhizin with angiotensin-converting enzyme inhibitor

A 77-year-old man with a history of hypertension and hyperuricemia was admitted to our hospital complaining of limb weakness, persistent constipation, and worsening hypertension. He had been taking a Chinese herbal remedy for allergic rhinitis for the past 10 years, together with an angiotensin-converting enzyme inhibitor (ACE-I; enalapril, 20 mg daily). After the dosage of enalapril had been reduced to 10 mg daily about 1(1/2) years before the current admission, he had developed persistent constipation. Therefore, he had started taking another traditional Chinese herbal remedy, a laxative, for the constipation, about 4 months prior to this hospitalization. Laboratory data on admission demonstrated marked metabolic alkalosis with severe hypokalemia associated with urinary wasting of potassium and chloride. A diagnosis of pseudoaldosteronism was made based upon his past history of exposure to various traditional Chinese medicines containing glycyrrhizin. Discontinuation of the Chinese remedies and supplementation of potassium successfully normalized the electrolyte imbalance and relieved all symptoms within a short time. The present case describes the occurrence of pseudoaldosteronism induced by a patient taking two traditional Chinese herbs, both containing glycyrrhizin, resulting in an overdose of this causative chemical agent. The development of pseudoaldosteronism appeared to be of particular interest with regard to the interaction of the renin-angiotensin-aldosterone (RAA) system with glycyrrhizin, in which an ACE-I retarded the development of pseudoaldosteronism.

[Some aspects of the antiarrhythmic effect of glialin]

The antiarrhythmic activity of allapinine and glialin (a complex of allapinin and glycyrrhizic acid) was studied on models of arrhythmias induced in rats and guinea pigs by intravenous administration of calcium chloride, aconitine, barium chloride, and strophanthin. The antiarrhythmic activity of glialin is qualitatively analogous to that of allapinine. The advantage of glialin over allapinin is its low toxicity, which is due to the presence of glycyrrhizic acid.

Exogenously-induced apparent hypermineralocorticoidism associated with ingestion of "asam boi"

A 31-year-old woman presented with a one-week history of headache, generalised lethargy, weakness and poor appetite. Clinical examination showed that her blood pressure was 200/120 mmHg. On an earlier occasion, her blood pressure was found to be normal by a general practitioner whom she last visited three months earlier when she had an upper respiratory tract infection. Investigations showed hypokalaemia, suppressed serum renin and aldosterone. Further history was taken and revealed that she had been craving for guava fruits which she ate with flavoured "asam boi" (containing glycyrrhizic acid) at least three spoonfuls twice a day for the past six weeks. The hypertension and hypokalaemia resolved after two weeks of stopping the "asam boi". Her clinical picture was compatible with exogenously-induced hypermineralocortoidism.

A case of pseudoaldosteronism, accompanied with hypocalcemia and exaggerated ACTH response

Glycyrrhizic acid (GA) inhibits the activity of 11beta-hydroxysteroid dehydrogenase type 2 in the kidney, with the resulting increase in intrarenal cortisol concentration leading to hypertension and suppression of the renin-aldosterone system. In this paper we describe an interesting case of pseudoaldosteronism, associated with hypocalcemia and an exaggerated ACTH response. A 72-year-old woman was referred to our department for further evaluation of hypokalemia and hypocalcemia. The patient had been taking GA (150 mg/day) for the previous year for treatment of liver damage. Plasma renin activity and aldosterone concentration were both within lower normal limits. Urinary excretion of potassium and calcium was within the upper limit of the normal range and increased with administration of supplements. Plasma ACTH levels increased markedly in response to an intravenous injection of CRH. Cessation of GA and the potassium and calcium supplements on admission, led to a gradual normalization of serum potassium and calcium levels and blood pressure. The hypocalcaemia in our patient was related to decreased tubular reabsorption of calcium as a consequence of renal corticoid excess. It is possible that an increase in the number of CRH receptors in the pituitary following GA treatment caused the exaggerated ACTH response in association with pseudoaldosteronism. The existence of hypocalcemia and an exaggerated ACTH response should be observed carefully when managing pseudoaldosteronism.

'Pseudo-aldosteronism' induced by intravenous glycyrrhizin treatment of chronic hepatitis C patients

BACKGROUND AND AIMS

Treatment with intravenous glycyrrhizin reduces the progression of liver disease caused by chronic hepatitis C (HCV) infection. Glycyrrhetinic acid, a metabolite of glycyrrhizin, inhibits the renal conversion of cortisol to cortisone by inhibiting the enzyme 11 beta-hydroxysteroiddehydrogenase in the kidney. The resulting excess of cortisol subsequently stimulates the mineralocorticoid receptor, leading to pseudo-aldosteronism with hypertension, hypokalemia and eventually renin and aldosterone suppression. The aim of this study was to evaluate the occurrence of pseudo-aldosteronism after treatment of chronic hepatitis C (HCV) patients with increasing doses of intravenous glycyrrhizin.

METHODS

Forty-four HCV patients with chronic hepatitis or compensated cirrhosis were treated with intravenous glycyrrhizin 6 x 200 mg/week, 3 x 240 mg/week or 3 x 0 mg/week (placebo) for 4 weeks. In all patients, bodyweight, blood pressure and plasma concentrations of sodium, potassium, cortisol, DHEA-S (dehydroepiandrosterone sulfate), renin and aldosterone were measured before, and at 0 and 4 weeks after treatment.

RESULTS

Within the placebo group, no significant changes were observed. Within the 1200 mg group systolic blood pressure was significantly higher at the end of treatment, while aldosterone was significantly lower; at the end of the follow-up period these values had returned to baseline. The changes from baseline in systolic and diastolic blood pressure at the end of treatment were significantly higher in the 1200 mg group compared to the placebo group. The changes in aldosterone and potassium concentrations at the end of treatment increased with increasing dosage, although not significantly.

CONCLUSION

Hepatitis C virus patients with chronic hepatitis or compensated cirrhosis show minor reversible symptoms of pseudo-aldosteronism after treatment with 1200 mg glycyrrhizin weekly for 4 weeks.

A human physiologically-based model for glycyrrhzic acid, a compound subject to presystemic metabolism and enterohepatic cycling

PURPOSE

To analyze the role of the kinetics of glycyrrhizic acid (GD) in its toxicity. A physiologically-based pharmacokinetic (PBPK) model that has been developed for humans.

METHODS

The kinetics of GD, which is absorbed as glycyrrhetic acid (GA), were described by a human PBPK model, which is based on a rat model. After rat to human extrapolation, the model was validated on plasma concentration data after ingestion of GA and GD solutions or licorice confectionery, and an additional data derived from the literature. Observed interindividual variability in kinetics was quantified by deriving an optimal set of parameters for each individual.

RESULTS

The a-priori defined model successfully forecasted GA kinetics in humans, which is characterized by a second absorption peak in the terminal elimination phase. This peak is subscribed to enterohepatic cycling of GA metabolites. The optimized model explained most of the interindividual variance, observed in the clinical study, and adequately described data from the literature.

CONCLUSIONS

Preclinical information on GD kinetics could be incorporated in the human PBPK model. Model simulations demonstrate that especially in subjects with prolonged gastrointestinal residence times, GA may accumulate after repeated licorice consumption, thus increasing the health risk of this specific subgroup of individuals.

Liquorice and its health implications

This article presents an overview of the health implications of liquorice. Liquorice has beneficial applications in the medicinal and the confectionery sectors; the substance, therefore, is both widely available and commercially attractive. However, the ingestion of liquorice, and/or its active metabolites, can sometimes produce an acquired form of apparent mineralocorticoid excess (AME) syndrome, expressed as sodium retention, potassium loss and suppression of the renin-angiotensin-aldosterone system, in addition to clinical consequences such as raised blood pressure and oedema. Moreover, these metabolic changes, the mechanisms underlying which are highlighted in the accompanying text, are associated with a number of additional clinical symptoms. Considering the easy availability of liquorice itself and also of other products containing its active metabolites, it is quite possible that the health burden of liquorice-induced morbidity could be substantial. Healthcare practitioners need to be fully aware of the risks in view of a large number of reports in the literature concerning its toxicity.

Gas chromatographic-mass spectrometric analysis of urinary glycyrrhetinic acid: an aid in diagnosing liquorice abuse

OBJECTIVES

Liquorice abuse can lead to severe clinical complications, caused by its active compound 18beta-glycyrrhetinic acid (18betaGA). 18betaGA inhibits dehydrogenase activity of 11beta-hydroxysteroid dehydrogenase (11betaHSD). This enzyme catalyses the interconversion between cortisol and cortisone and normally protects the mineralocorticoid receptor from being activated by cortisol. Diagnosing liquorice abuse can be notoriously difficult. The aim of our study was to develop an accurate and clinically applicable 18betaGA urinary assay.

DESIGN

We developed a urinary 18betaGA assay based on gas chromatography and mass spectrometry (GCMS) with sufficient sensitivity to detect 18betaGA at low concentrations. The assay was validated in four volunteers consuming different amounts of liquorice. We applied its use in two patients with hypokalaemic hypertension and suppressed plasma renin activity and serum aldosterone, who were suspected of liquorice abuse.

RESULTS

The detection limit for 18betaGA of the GC assay was 10 microg L-1, which was lowered to 3 microg L-1 by subsequent application of MS. In all volunteers, urinary 18betaGA was detected during liquorice intake. Urinary 18betaGA remained detectable until 5 days after stopping continued liquorice intake and until at least 51 h after ingestion of a single large amount. Urinary 18betaGA was demonstrated in both patients, establishing a diagnosis of liquorice abuse. One patient showed changes in urinary cortisol metabolites, consistent with 11betaHSD inhibition. Changes in cortisol metabolites were less pronounced in the other patient.

CONCLUSION

Liquorice abuse can result in hypokalaemic hypertension with prolonged suppression of plasma renin activity and aldosterone concentration. This is caused by 18betaGA-mediated inhibition of 11betaHSD, resulting in activation of the renal mineralocorticoid receptor by cortisol. Urinary 18betaGA measurement by GCMS is a useful aid in establishing liquorice abuse.

Combined ursodeoxycholic acid and glycyrrhizin therapy for chronic hepatitis C virus infection: a randomized controlled trial in 170 patients

OBJECTIVE AND DESIGN

To assess the efficacy and safety of combination therapy using ursodeoxycholic acid with glycyrrhizin for chronic hepatitis C virus infection, we conducted a prospective randomized controlled trial of glycyrrhizin (group G) compared with glycyrrhizin plus ursodeoxycholic acid (group G+U) in 170 patients.

METHODS

All patients had elevated serum aminotransferase levels over 6 months before entry into the trial. Glycyrrhizin was administered to both groups for 24 weeks, and in group G+U, ursodeoxycholic acid (600 mg/day) was administered orally as well.

RESULTS

Serum aspartate transaminase and alanine transaminase concentrations significantly decreased during treatment in both groups, but serum gamma-glutamyl transpeptidase concentrations fell significantly only in group G+U. Concentrations of all three enzymes fell significantly more in group G+U than in group G, and had normalized in more cases when the trial ended at 24 weeks. However, levels of HCV viraemia did not change during the trial in either group. Multiple regression analysis linked only the treatment regimen, not HCV-related factors or liver histology, to the degree of serum enzyme reduction. No adverse effects were noted in either group.

CONCLUSIONS

The combined therapy with ursodeoxycholic acid and glycyrrhizin is safe and effective in improving liver-specific enzyme abnormalities, and may be an alternative to interferon in chronic hepatitis C virus infection, especially for interferon-resistant or unstable patients.

Effects of absorption enhancers on cytoskeletal actin filaments in Caco-2 cell monolayers

Histomorphological changes of actin filaments, intracellular levels of calcium ion, and amount of released lactate dehydrogenase (LDH) were examined, in order to elucidate the mechanism of action of three absorption enhancers, i.e., sodium caprate (Cap-Na), sodium deoxycholate (Deo-Na), and dipotassium glycyrrhizinate (Grz-K), using Caco-2 cell monolayers. The structure of actin filaments in microvilli was slightly modified by 0.5 %(w/v) Grz-K and was significantly changed by 0.2 %(w/v) Cap-Na, 0.05 %(w/v) Deo-Na, and 0.0015 %(w/v) ionomycin. All of the enhancers, except Grz-K, induced significantly histomorphological changes in the actin filaments on the middle depth and basal side of the cells. Furthermore, the altered structure of the actin filaments in the monolayers was restored after removal of the Cap-Na, Grz-K and ionomycin, but not Deo-Na. Intracellular levels of calcium ion increased in the following order: ionomycin = Cap-Na > Deo-Na. However, the intracellular calcium ion levels decreased by treatment with Grz-K. The changes in transepithelial electric resistance (TEER) at the initial stage of treatment with all enhancers correlated with intracellular calcium ion levels. These results suggest that one of the mechanisms by which these agents exert absorption-enhancing activity involves structural alterations in the cytoskeletal actin filaments which are provoked by changes in intracellular calcium ion levels. Only the monolayers which were treated with 0.05 %(w/v) Deo-Na released a significant amount of LDH and irreversibly altered the structure of actin filaments, thus indicating that Deo-Na might affect the actin filaments not only by increasing intracellular calcium ion level but also by other, presently unknown factors.