Total alditols from Cistanche deserticola attenuate functional constipation by regulating bile acid metabolism

HEADINGS ETHNOPHARMACOLOGICAL RELEVANCE

Functional constipation (FC), characterized by chronic constipation, significantly impacts physiological function and induces psychological stress in patients. However, current clinical treatment options for FC are currently limited. Cistanche deserticola, a traditional Chinese medicine that promotes intestinal moisture and bowel relaxation, contains cistanche total alditol extract (CTAE) as its primary active extract. However, the production of CTAE, its overall efficacy, and potential mechanisms for treating FC have yet to been investigated.

AIM OF THE STUDY

This study aimed to reveal the overall efficacy and potential mechanism of action of CTAE in rats with FC using a combination of stable preparation, pharmacodynamics, non-targeted metabolomics, bile acid metabolomics, and western blotting.

MATERIALS AND METHODS

Fourteen batches of CTAE underwent quality testing. A rat model of FC was developed using diphenoxylate tablets. The comprehensive pharmacodynamic effects of CTAE on FC were evaluated using fecal characteristics (wet weight, dry weight, and water content), intestinal transmission (colonic EMG amplitude, colonic EMG frequency, propulsion length, and propulsion rate), serum and colon biochemical indicators, distribution of interstitial cells of Cajal (ICC), and pathological examination. Non-targeted metabolomics was performed to assess the changes in endogenous metabolite profiles induced by CTAE. Bile acid metabolomics and western blotting analyses were employed to validate the potential mechanisms of action of CTAE.

RESULTS

CTAE, with a total content of betaine, mannitol, D-fructose, glucose, and sucrose of (75.67 ± 3.73) %, significantly enhanced intestinal transit, regulated neurotransmitters, increased the expression of c-kit in ICC, and alleviated intestinal inflammation in rats with FC. Non-targeted metabolomics revealed that CTAE significantly alleviated FC-induced metabolic disorders, mainly the biosynthesis of primary bile acids. Targeted metabolomic analysis confirmed that CTAE regulated FC-induced bile acid disorders. Western-blotting results confirmed that CTAE increased the expression of CYP8B1, FGF15, TGR5, and FXR, thereby modulating bile acid synthesis and enterohepatic circulation.

CONCLUSION

CTAE demonstrates significant therapeutic effects on FC, primarily through the regulation of bile acid synthesis and enterohepatic circulation. These findings provide a promising foundation for the development and clinical application of novel CATE-based drugs.

Biological Activities of Lactose-Derived Prebiotics and Symbiotic with Probiotics on Gastrointestinal System

Lactose-derived prebiotics provide wide ranges of gastrointestinal comforts. In this review article, the probable biochemical mechanisms through which lactose-derived prebiotics offer positive gastrointestinal health are reported along with the up-to-date results of clinical investigations; this might be the first review article of its kind, to the best of our knowledge. Lactose-derived prebiotics have unique biological and functional values, and they are confirmed as ‘safe’ by the Food and Drug Administration federal agency. Medical practitioners frequently recommend them as therapeutics as a pure form or combined with dairy-based products (yoghurt, milk and infant formulas) or fruit juices. The biological activities of lactose-derived prebiotics are expressed in the presence of gut microflora, mainly probiotics (Lactobacillus spp. in the small intestine and Bifidobacterium spp. in the large intestine). Clinical investigations reveal that galacto-oligosaccharide reduces the risks of several types of diarrhea (traveler’s diarrhea, osmotic diarrhea and Clostridium difficile associated relapsing diarrhea). Lactulose and lactosucrose prevent inflammatory bowel diseases (Crohn’s disease and ulcerative colitis). Lactulose and lactitol reduce the risk of hepatic encephalopathy. Furthermore, lactulose, galacto-oligosaccharide and lactitol prevent constipation in individuals of all ages. It is expected that the present review article will receive great attention from medical practitioners and food technologists.

The caries preventive effect of 1-year use of low-dose xylitol chewing gum. A randomized placebo-controlled clinical trial in high-caries-risk adults

Objectives

The caries preventive effect of long-term use (1 year) of low-dosage (2.5 g/die) of xylitol chewing gum in a high-caries-risk adult population was evaluated.

Materials and methods

In this randomized clinical trial, 179 high-caries-risk adults were assigned to two experimental groups, xylitol and polyols. Caries status, salivary mutans streptococci (MS), and plaque pH were re-evaluated after 2 years from baseline in 66 xylitol and 64 polyol subjects. Outcomes (the net caries increment for initial, moderate, and extensive caries lesions and for the caries experience) were evaluated using the nonparametric Mann–Whitney U test.

Results

The total caries experience increment was 1.25 ± 1.26 in the xylitol group and 1.80 ± 2.33 in the polyol group (p = 0.01). Subjects treated with xylitol chewing gums had a reduction of risk rate at tooth level of 23% with respect to those treated with polyols with a number needed to treat of 55 teeth. The area under the curve at pH 5.7 was statistically significantly lower (p = 0.02) during the experimental period in the xylitol group. A decrease of the concentration of salivary MS was noted in the xylitol group (p < 0.01).

Conclusions

Subjects using the low-dose xylitol chewing gum showed a significantly lower increment of initial and extensive caries lesions and overall a lower increment of caries experience.

Clinical relevance

One-year use of chewing gums provides an effective means for the prevention of caries disease.

Trial registration number

NCT02310308

Current state of knowledge of hepatic encephalopathy (part III): non-absorbable disaccharides

Nonabsorbable disaccharides have been the mainstay of treatment for hepatic encephalopathy since introduced into clinical practice in 1966. Their beneficial effects reflect their ability to reduce the intestinal production/absorption of ammonia. A recent Cochrane review confirmed the efficacy and safety of nonabsorbable disaccharides for the treatment and prevention of hepatic encephalopathy in patients with cirrhosis. The findings were robust and support the use of nonabsorbable disaccharides as a first line treatment for hepatic encephalopathy, in this patient population, and for its prevention.

Non-absorbable disaccharides versus placebo/no intervention and lactulose versus lactitol for the prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Non-absorbable disaccharides (lactulose and lactitol) are recommended as first-line treatment for hepatic encephalopathy. The previous (second) version of this review included 10 randomised clinical trials (RCTs) evaluating non-absorbable disaccharides versus placebo/no intervention and eight RCTs evaluating lactulose versus lactitol for people with cirrhosis and hepatic encephalopathy. The review found no evidence to either support or refute the use of the non-absorbable disaccharides and no differences between lactulose versus lactitol.

OBJECTIVES

To assess the beneficial and harmful effects of i) non-absorbable disaccharides versus placebo/no intervention and ii) lactulose versus lactitol in people with cirrhosis and hepatic encephalopathy.

SEARCH METHODS

We carried out electronic searches of the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 10), MEDLINE, EMBASE, and Science Citation Index Expanded to 19 October 2015; manual searches of meetings and conference proceedings; checks of bibliographies; and correspondence with investigators and pharmaceutical companies.

SELECTION CRITERIA

We included RCTs, irrespective of publication status, language, or blinding.

DATA COLLECTION AND ANALYSIS

Two review authors, working independently, retrieved data from published reports and correspondence with investigators. The primary outcomes were mortality, hepatic encephalopathy, and serious adverse events. We presented the results of meta-analyses as risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI). We assessed the quality of the evidence using 'Grading of Recommendations Assessment Development and Evaluation' (GRADE) and bias control using the Cochrane Hepato-Biliary Group domains. Our analyses included regression analyses of publication bias and other small study effects, Trial Sequential Analyses to detect type 1 and type 2 errors, and subgroup and sensitivity analyses.

MAIN RESULTS

We included 38 RCTs with a total of 1828 participants. Eight RCTs had a low risk of bias in the assessment of mortality. All trials had a high risk of bias in the assessment of the remaining outcomes. Random-effects meta-analysis showed a beneficial effect of non-absorbable disaccharides versus placebo/no intervention on mortality when including all RCTs with extractable data (RR 0.59, 95% CI 0.40 to 0.87; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence) and in the eight RCTs with a low risk of bias (RR 0.63, 95% CI 0.41 to 0.97; 705 participants). The Trial Sequential Analysis with the relative risk reduction (RRR) reduced to 30% confirmed the findings when including all RCTs, but not when including only RCTs with a low risk of bias or when we reduced the RRR to 22%. Compared with placebo/no intervention, the non-absorbable disaccharides were associated with beneficial effects on hepatic encephalopathy (RR 0.58, 95% CI 0.50 to 0.69; 1415 participants; 22 RCTs; I(2) = 32%; moderate quality evidence). Additional analyses showed that non-absorbable disaccharides can help to reduce serious adverse events associated with the underlying liver disease including liver failure, hepatorenal syndrome, and variceal bleeding (RR 0.47, 95% CI 0.36 to 0.60; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence). We confirmed the results in Trial Sequential Analysis. Tests for subgroup differences showed no statistical differences between RCTs evaluating prevention, overt, or minimal hepatic encephalopathy. The evaluation of secondary outcomes showed a potential beneficial effect of the non-absorbable disaccharides on quality of life, but we were not able to include the data in an overall meta-analysis (very low quality evidence). Non-absorbable disaccharides were associated with non-serious (mainly gastrointestinal) adverse events (very low quality evidence). None of the RCTs comparing lactulose versus lactitol evaluated quality of life. The review found no differences between lactulose and lactitol for the remaining outcomes (very low quality evidence).

AUTHORS' CONCLUSIONS

This review includes a large number of RCTs evaluating the prevention or treatment of hepatic encephalopathy. The analyses found evidence that non-absorbable disaccharides may be associated with a beneficial effect on clinically relevant outcomes compared with placebo/no intervention.

Non-absorbable disaccharides versus placebo/no intervention and lactulose versus lactitol for the prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Non-absorbable disaccharides (lactulose and lactitol) are recommended as first-line treatment for hepatic encephalopathy. The previous (second) version of this review included 10 randomised clinical trials (RCTs) evaluating non-absorbable disaccharides versus placebo/no intervention and eight RCTs evaluating lactulose versus lactitol for people with cirrhosis and hepatic encephalopathy. The review found no evidence to either support or refute the use of the non-absorbable disaccharides and no differences between lactulose versus lactitol.

OBJECTIVES

To assess the beneficial and harmful effects of i) non-absorbable disaccharides versus placebo/no intervention and ii) lactulose versus lactitol in people with cirrhosis and hepatic encephalopathy.

SEARCH METHODS

We carried out electronic searches of the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 10), MEDLINE, EMBASE, and Science Citation Index Expanded to 19 October 2015; manual searches of meetings and conference proceedings; checks of bibliographies; and correspondence with investigators and pharmaceutical companies.

SELECTION CRITERIA

We included RCTs, irrespective of publication status, language, or blinding.

DATA COLLECTION AND ANALYSIS

Two review authors, working independently, retrieved data from published reports and correspondence with investigators. The primary outcomes were mortality, hepatic encephalopathy, and serious adverse events. We presented the results of meta-analyses as risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI). We assessed the quality of the evidence using 'Grading of Recommendations Assessment Development and Evaluation' (GRADE) and bias control using the Cochrane Hepato-Biliary Group domains. Our analyses included regression analyses of publication bias and other small study effects, Trial Sequential Analyses to detect type 1 and type 2 errors, and subgroup and sensitivity analyses.

MAIN RESULTS

We included 38 RCTs with a total of 1828 participants. Eight RCTs had a low risk of bias in the assessment of mortality. All trials had a high risk of bias in the assessment of the remaining outcomes. Random-effects meta-analysis showed a beneficial effect of non-absorbable disaccharides versus placebo/no intervention on mortality when including all RCTs with extractable data (RR 0.59, 95% CI 0.40 to 0.87; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence) and in the eight RCTs with a low risk of bias (RR 0.63, 95% CI 0.41 to 0.97; 705 participants). The Trial Sequential Analysis with the relative risk reduction (RRR) reduced to 30% confirmed the findings when including all RCTs, but not when including only RCTs with a low risk of bias or when we reduced the RRR to 22%. Compared with placebo/no intervention, the non-absorbable disaccharides were associated with beneficial effects on hepatic encephalopathy (RR 0.58, 95% CI 0.50 to 0.69; 1415 participants; 22 RCTs; I(2) = 32%; moderate quality evidence). Additional analyses showed that non-absorbable disaccharides can help to reduce serious adverse events associated with the underlying liver disease including liver failure, hepatorenal syndrome, and variceal bleeding (RR 0.47, 95% CI 0.36 to 0.60; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence). We confirmed the results in Trial Sequential Analysis. Tests for subgroup differences showed no statistical differences between RCTs evaluating prevention, overt, or minimal hepatic encephalopathy. The evaluation of secondary outcomes showed a potential beneficial effect of the non-absorbable disaccharides on quality of life, but we were not able to include the data in an overall meta-analysis (very low quality evidence). Non-absorbable disaccharides were associated with non-serious (mainly gastrointestinal) adverse events (very low quality evidence). None of the RCTs comparing lactulose versus lactitol evaluated quality of life. The review found no differences between lactulose and lactitol for the remaining outcomes (very low quality evidence).

AUTHORS' CONCLUSIONS

This review includes a large number of RCTs evaluating the prevention or treatment of hepatic encephalopathy. The analyses found evidence that non-absorbable disaccharides may be associated with a beneficial effect on clinically relevant outcomes compared with placebo/no intervention.

Effects of maltitol and xylitol chewing-gums on parameters involved in dental caries development

AIM

The effects on plaque parameters of sugar free chewing-gums (CG) sweetened with either maltitol or xylitol were assessed to better understand the role polyols can play in dental caries prevention.

MATERIALS AND METHODS

A double-blind, parallel, randomised, controlled study was conducted in China. Subjects (N = 258, age = 13 to 15 years-old) were divided into 4 groups: 2 receiving polyols CG, containing respectively maltitol or xylitol, a group receiving gum base (placebo) and a negative control group not receiving any gum. CG were chewed for 30 days. This corresponds to a 10 g consumption of polyol per day. Plaque parameters (growth, pH, bacteria and insoluble glucans) were evaluated throughout the experimental period.

RESULTS

All parameters studied were significantly modified with gum base compared to no-gum: plaque pH increased; plaque growth, bacteria (S. mutans, S. sobrinus, A. viscosus and Lactobacillus) and insoluble glucans decreased. Maltitol and xylitol CG led similarly to a higher plaque pH (AUC, p⋜0.05) on short (at baseline after the first CG consumption) and long term (after 4 weeks of daily CG consumption), with or without saliva stimulation compared to both control and placebo groups. They led to a decrease in plaque growth (p=0.02) over the experimental period compared to controls. Moreover, they significantly reduced the concentration of 4 cariogenic bacteria species (p⋜0.05) in dental plaque compared to gum base.

CONCLUSION

Sugar free CG sweetened with either maltitol or xylitol can similarly reduce plaque acidogenicity compared to gum base through a decrease in oral bacteria presence. The use of a gum base placebo allowed to isolate effects on parameters involved in dental caries development specific to maltitol and xylitol, and to show these effects were similar.

Disaccharides in the treatment of hepatic encephalopathy

Management of hepatic encephalopathy (HE) primarily involves avoidance of precipitating factors and administration of various ammonia-lowering therapies such as nonabsorbable disaccharides and antimicrobial agents like rifaximin. The nonabsorbable disaccharides which include lactulose and lactitol are considered the first-line therapy for the treatment of HE and minimal hepatic encephalopathy (MHE). Lactulose significantly improves cognitive function and health-related quality of life in patients with MHE. Lactitol is comparable to lactulose in the treatment of HE with fewer side effects. Lactulose has also shown to be effective in primary and secondary prophylaxis of HE. Disaccharides were found to be comparable to rifaximin in recent systemic reviews in the treatment of HE however conclusion was based on inclusion of some poor quality trials. Combination therapy of disaccharides either with rifaximin, L-ornithine L-aspartate,probiotics for the treatment of HE needs further validation in large studies.

Osmotic and stimulant laxatives for the management of childhood constipation

BACKGROUND

Constipation within childhood is an extremely common problem. Despite the widespread use of osmotic and stimulant laxatives by health professionals to manage constipation in children, there has been a long standing paucity of high quality evidence to support this practice.

OBJECTIVES

We set out to evaluate the efficacy and safety of osmotic and stimulant laxatives used to treat functional childhood constipation.

SEARCH METHODS

The search (inception to May 7, 2012) was standardised and not limited by language and included electronic searching (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Inflammatory Bowel Disease and Functional Bowel Disorders Group Specialized Trials Register), reference searching of all included studies, personal contacts and drug companies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) which compared osmotic or stimulant laxatives with either placebo or another intervention, with patients aged 0 to 18 years old were considered for inclusion. The primary outcome was frequency of defecation. Secondary endpoints included faecal incontinence, disimpaction, need for additional therapies and adverse events.

DATA COLLECTION AND ANALYSIS

Relevant papers were identified and the authors independently assessed the eligibility of trials. Methodological quality was assessed using the Cochrane risk of bias tool.The Cochrane RevMan software was used for analyses. Patients with final missing outcomes were assumed to have relapsed. For continuous outcomes we calculated a mean difference (MD) and 95% confidence interval (CI) using a fixed-effect model. For dichotomous outcomes we calculated an odds ratio (OR) and 95% confidence intervals (95% CI) using a fixed-effect model. The chi square and I(2) statistics were used to assess statistical heterogeneity. A random-effects model was used in situations of unexplained heterogeneity

MAIN RESULTS

Eighteen RCTs (1643 patients) were included in the review. Nine studies were judged to be at high risk of bias due to lack of blinding, incomplete outcome data and selective reporting. Meta-analysis of two studies (101 patients) comparing polyethylene glycol (PEG) with placebo showed a significantly increased number of stools per week with PEG (MD 2.61 stools per week, 95% CI 1.15 to 4.08). Common adverse events in the placebo-controlled studies included flatulence, abdominal pain, nausea, diarrhoea and headache. Meta-analysis of 4 studies with 338 participants comparing PEG with lactulose showed significantly greater stools per week with PEG (MD 0.95 stools per week, 95% CI 0.46 to 1.44), although follow up was short. Patients who received PEG were significantly less likely to require additional laxative therapies. Eighteen per cent of PEG patients required additional therapies compared to 30% of lactulose patients (OR 0.49, 95% CI 0.27 to 0.89). No serious adverse events were reported with either agent. Common adverse events in these studies included diarrhoea, abdominal pain, nausea, vomiting and pruritis ani. Meta-analysis of 3 studies with 211 participants comparing PEG with milk of magnesia showed that the stools/wk was significantly greater with PEG (MD 0.69 stools per week, 95% CI 0.48 to 0.89). However, the magnitude of this difference is quite small and may not be clinically significant. One child was noted to be allergic to PEG, but there were no other serious adverse events reported. Meta-analysis of 2 studies with 287 patients comparing liquid paraffin (mineral oil) with lactulose revealed a relatively large statistically significant difference in the number of stools per week favouring paraffin (MD 4.94 stools per week, 95% CI 4.28 to 5.61). No serious adverse events were reported. Adverse events included abdominal pain, distention and watery stools. No statistically significant differences in the number of stools per week were found between PEG and enemas (1 study, 90 patients, MD 1.00, 95% CI -1.58 to 3.58), dietary fibre mix and lactulose (1 study, 125 patients, P = 0.481), senna and lactulose (1 study, 21 patients, P > 0.05), lactitol and lactulose (1 study, 51 patients, MD -0.80, 95% CI -2.63 to 1.03), and PEG and liquid paraffin (1 study, 158 patients, MD 0.70, 95% CI -0.38 to 1.78).

AUTHORS' CONCLUSIONS

The pooled analyses suggest that PEG preparations may be superior to placebo, lactulose and milk of magnesia for childhood constipation. GRADE analyses indicated that the overall quality of the evidence for the primary outcome (number of stools per week) was low or very low due to sparse data, inconsistency (heterogeneity), and high risk of bias in the studies in the pooled analyses. Thus, the results of the pooled analyses should be interpreted with caution because of quality and methodological concerns, as well as clinical heterogeneity, and short follow up. However, PEG appears safe and well tolerated. There is also evidence suggesting the efficacy of liquid paraffin (mineral oil), which was also well tolerated.There is no evidence to demonstrate the superiority of lactulose when compared to the other agents studied, although there is a lack of placebo controlled studies. Further research is needed to investigate the long term use of PEG for childhood constipation, as well as the role of liquid paraffin.

Lactitol or lactulose in the treatment of chronic constipation: result of a systematic

Constipation is a common problem for adults and paediatric patients and can generate considerable suffering for patients due to both the unpleasant physical symptoms and psychological preoccupations that can arise. Since disaccharide sugar is widely prescribed osmotic laxative in India, we decided to do systematic review to compare the efficacy and safety of lactitol versus lactulose in the management of constipation. All randomised, non-randomised and open trials, with head to head comparison of lactitol versus lactulose were included. After intense literature search we included six clinical trials for comparison. The relevant studies that were included in meta-analysis included 349 adult patients with mean age group of 19 to 85 years and 81 children from age group of 8 months to 16 years. Duration of treatment was 3 days to 4 weeks. In terms of efficacy lactitol was found to be comparable to lactulose in terms of normal consistency of stool and number of bowel movement per week. Better acceptance by the patients was reported with lactitol as compared to lactulose (73.2% versus 26.8%). Lactitol was found to be significantly superior as compared to lactulose in terms of less number of adverse events (31.20 +/- 0.8000% versus 62.10 +/-1.100%, p = 0.0019). Better efficacy was adjudged by the physicians in favour of lactitol as compared to lactulose (61.91% versus 47.83%). In addition compliance with lactitol was found to be better due to superior palatability. Also in paediatric patients the dose of lactitol required was almost half the dose of lactulose (250-400 mg/kg/day versus 500-750 mg/kg/day). Lactitol should be preferred over lactulose in the management of chronic constipation because of its superior efficacy as adjudged by the physician, better palatability, lesser incidence of adverse events, better acceptance and compliance reported by patients.

Improved metabolic control after 12-week dietary intervention with low glycaemic isomalt in patients with type 2 diabetes mellitus

The polyol isomalt (Palatinit) is a very low glycaemic sugar replacer. The effect of food supplemented with isomalt instead of higher glycaemic ingredients like sucrose and/or starch hydrolysates on metabolic control in patients with type 2 diabetes was examined in this open study. Thirty-three patients with type 2 diabetes received a diet with foods containing 30 g/d isomalt instead of higher-glycaemic carbohydrates for 12 weeks. Metformin and/or thiazolidindiones were the only concomitant oral antidiabetics allowed during the study. Otherwise, the participants maintained their usual diet during the test phase, but were instructed to refrain from additional sweetened foods. Before start, after 6 weeks and 12 weeks (completion of the study), blood samples were taken and analysed for clinical routine parameters, metabolic, and risk markers. Thirty-one patients completed the study. The test diet was well accepted and tolerated. After 12 weeks, significant reductions were observed for: glycosylated haemoglobin, fructosamine, fasting blood glucose, insulin, proinsulin, C-peptide, insulin resistance (HOMA-IR), and oxidised LDL (an atherosclerosis risk factor). In addition, significant lower nonesterified fatty acid concentrations were found in female participants. Routine blood measurements and blood lipids remained unchanged. The substitution of glycaemic ingredients by isomalt and the consequent on reduction of the glycaemic load within otherwise unchanged diet was accompanied by significant improvement in the metabolic control of diabetes. The present study is in agreement with findings of previous reported studies in human subjects demonstrating beneficial effects of low glycaemic diets on glucose metabolism in patients with diabetes mellitus type 2.

[Elderly hereditary hemorrhagic telangiectasia female with portosystemic encephalopathy]

We present a 71-year-old woman with hereditary hemorrhagic telangiectasia (HHT) who at age 69, had undergone total gastrectomy because of repeated upper gastrointestinal bleeding. A day prior to admission she began to demonstrate abnormal behavior. Examination showed she was restless and had higher brain dysfunction. Triphasic waves were seen on EEG, and a high signal in the globus pallidus on T1-weighted MRI. Plasma NH3 level was increased after a meal. Abdominal CT scan showed vascular anomalies including a portohepatic vein shunt. She was diagnosed with portosystemic encephalopathy. After treatment with a low-protein diet, lactitol, and branched chain-amino acids, her clinical condition, plasma NH3 level after a meal, and EEG returned to normal. Because portosystemic shunt is rare in HHT, there have been few reports of portosystemic encephalopathy with this condition. However, with aging, the possibility of portosystemic encephalopathy increases because of age-related increases in portosystemic shunt volume.

The treatment of hepatic encephalopathy

Current recommendations for the treatment of hepatic encephalopathy are based, to a large extent, on open or uncontrolled trials, undertaken in very small numbers of patients. In consequence, there is ongoing discussion as to whether the classical approach to the treatment of this condition, which aims at reducing ammonia production and absorption using either non-absorbable disaccharides and/or antibiotics, should be revisited, modified or even abandoned. Pros and cons of present therapeutic strategies and possible future developments were discussed at the fourth International Hannover Conference on Hepatic Encephalopathy held in Dresden in June 2006. The content of this discussion is summarized.

[A case of recurrent pneumatosis cystoides intestinalis associated with recurrent pneumoperitoneum]

Pneumatosis cystoides intestinalis is an uncommon condition of unknown etiology, characterized by the presence of multiple gas filled cysts in the gastrointestinal tract. Many different causes of pneumatosis cystoides intestinalis have been proposed, including mechanical, pulmonary, and bacterial causes. Approximately 85% of cases are thought to be secondary to coexisting disorders of the gastrointestinal tract or the respiratory system. The condition has been associated with the therapeutic uses of lactulose, steroids, and various cancer chemotherapeutic regimens. Lactitol is a disaccharide analogue of lactulose which is available as a pure crystalline powder. There are three previous case reports suggestive of lactulose causing pneumatosis intestinalis. We report a case of recurrent pneumatosis cystoides intestinalis associated with benign recurrent pneumoperitoneum developed probably secondary to lactitol therapy.

Effects of lactitol on intestinal microflora and plasma endotoxin in patients with chronic viral hepatitis

OBJECTIVES

To investigate the effects of lactitol on intestinal flora and the levels of plasma endotoxin in patients with chronic viral hepatitis.

METHODS

Sixty patients with chronic viral hepatitis and gut-derived endotoxemia were randomly divided into two groups: lactitol group (n=30) and control group (n=30). Patients in the control group received standard medical treatment for 3 weeks, while patients in the lactitol group received lactitol orally in addition to the standard medical treatment. Fecal flora and plasma endotoxin were measured before and after the treatment.

RESULTS

In the lactitol group, the numbers of Bifidobacterium and Lactobacillus per gram of wet feces were significantly increased (p<0.01) and Clostridium perfringens count was decreased markedly (p<0.001). The levels of plasma endotoxin decreased after the treatment from 72.89 ng/L to 33.33 ng/L in the lactitol group and from 66.00 ng/L to 51.07 ng/L in the control group, but the plasma endotoxin levels in the lactitol group decreased far more than in the control group (p<0.01).

CONCLUSIONS

Lactitol can decrease the levels of plasma endotoxin more effectively than standard medical treatment in patients with chronic viral hepatitis through improving intestinal microflora.

Effect of xylitol:sorbitol on fluoride enamel demineralization reduction in situ

OBJECTIVES

To evaluate if sugar alcohols would reduce enamel demineralization enhancing the fluoride (F) effect.

METHODS

A crossover in situ study was conducted in four phases, during which 10 volunteers were submitted to one of the treatments: (I) Distilled and deionized water, as a negative control; (II) F (226 microg F/ml as NaF; concentration used in commercial mouthrinse); (III) X:S (xylitol:sorbitol 1:3; final concentration 1.6M; 28% of sugar alcohols) and (IV) F+X:S (same final concentration that groups II and III). The volunteers wore palatal appliances containing four bovine enamel blocks of known surface microhardness (SMH), covered with a 'test plaque' of mutans streptococci, which were immersed during 1 min in one of the allocated treatment solutions simultaneously that the volunteers rinsed their mouths with the same solution. After the rinsing the appliances were put in the mouth and after 20 min a cariogenic challenge was made with 20% sucrose solution during 1 min. After further 45 min the 'test plaque' was collected for F analysis, enamel SMH was again determined and the percentage of change in relation to baseline was calculated; F uptake in enamel was also determined.

RESULTS

With respect to all the analyses made, the group F+X:S did not differ from the F treatment (p>0.05) and the groups treated with F and F+X:S differed from the negative control (p<0.05).

CONCLUSIONS

The results suggest that xylitol:sorbitol may not enhance the effect of fluoride present in mouth rinse on the reduction of enamel demineralization.

Xylitol, sweeteners, and dental caries

The purpose of this report was to provide an overview of xylitol and other polyol sweeteners and dental caries for clinicians and to discuss current applications for dental practice and potential community-based public health interventions. Xylitol, like other polyol sweeteners, is a naturally occurring sugar alcohol. Studies suggest polyols are noncariogenic. Furthermore, studies indicate that xylitol can decrease mutans streptococci levels in plaque and saliva and can reduce dental caries in young children, mothers, and in children via their mothers. Food products containing xylitol are now available and have the potential to be widely accessible to consumers to help control rampant decay. Determining whether products contain adequate xylitol amounts for practical use towards prevention is challenging, however, because xylitol content is not clearly labeled. Sufficient evidence exists to support the use of xylitol to reduce caries. Clinicians and dental associations should push for clear recommendations of efficacious dose and frequency of xylitol use and for clear labeling of xylitol content in products to help consumers choose appropriately.

Sugar Alcohols: What Is the Evidence for Caries-Preventive and Caries-Therapeutic Effects?

The most widely used sugar alcohols are: xylitol, sorbitol, mannitol, maltitol, lactitol and the products Lycasin and Palatinit. It is often claimed that xylitol is superior to the other sugar alcohols for caries control. This paper examines clinical studies on the caries-preventive and therapeutic effects of sugar alcohols with emphasis on sorbitol and xylitol. It is concluded that chewing sugar-free gum 3 or more times daily for prolonged periods of time may reduce caries incidence irrespective of the type of sugar alcohol used. It may be sufficient to do this only on school days. Sucking xylitol-containing candies or tablets may have a similar effect as chewing xylitol chewing gum. Clinical trials suggest greater caries reductions from chewing gums sweetened with xylitol than from gums sweetened with sorbitol. However, the superiority of xylitol was not confirmed in 2 out of 4 clinical trials comparing the caries-preventive effect of xylitol- with sorbitol-sweetened gums. The caries-preventive effects of polyol-containing gums and candies seem to be based on stimulation of the salivary flow, although an antimicrobial effect cannot be excluded. There is no evidence for a caries-therapeutic effect of xylitol. These conclusions are in line with those of recent reviews and with the conclusions of the Scientific Committee on Medicinal Products and Medical Devices of the EU Commission.

Non-absorbable disaccharides for hepatic encephalopathy: systematic review of randomised trials

OBJECTIVE

To assess the effects of non-absorbable disaccharides (lactulose and lactitol) in patients with hepatic encephalopathy.

DATA SOURCES

Cochrane Hepato-Biliary Group controlled trials register, Cochrane Library, Medline, and Embase until March 2003; reference lists of relevant articles; authors and pharmaceutical companies.

REVIEW METHODS

Randomised trials that compared non-absorbable disaccharides with placebo, no intervention, or antibiotics for hepatic encephalopathy were included. The primary outcome measures were no improvement of hepatic encephalopathy and all cause mortality.

RESULTS

22 trials were included. Compared with placebo or no intervention, non-absorbable disaccharides seemed to reduce the risk of no improvement in patients with hepatic encephalopathy (relative risk 0.62, 95% confidence interval 0.46 to 0.84, six trials). However, high quality trials found no significant effect (0.92, 0.42 to 2.04, two trials). Compared with placebo or no intervention, non-absorbable disaccharides had no significant effect on mortality (0.41, 0.02 to 8.68, four trials). Non-absorbable disaccharides were inferior to antibiotics in reducing the risk of no improvement (1.24, 1.02 to 1.50, 10 trials) and lowering blood ammonia concentration (weighted mean difference 2.35 micromol/l, 0.06 micromol/l to 13.45 micromol/l, 10 trials). There was no significant difference in mortality (0.90, 0.48 to 1.67, five trials).

CONCLUSIONS

There is insufficient evidence to support or refute the use of non-absorbable disaccharides for hepatic encephalopathy. Antibiotics were superior to non-absorbable disaccharides in improving hepatic encephalopathy, but it is unclear whether this difference is clinically important. Non-absorbable disaccharides should not serve as comparator in randomised trials on hepatic encephalopathy.

Nonabsorbable disaccharides for hepatic encephalopathy

BACKGROUND

Nonabsorbable disaccharides (lactulose or lactitol) are considered the treatment of choice for hepatic encephalopathy.

OBJECTIVES

To assess the beneficial and harmful effects of nonabsorbable disaccharides for patients with hepatic encephalopathy.

SEARCH STRATEGY

Trials were identified through The Cochrane Hepato-Biliary Group Controlled Trials Register (March 2003), The Cochrane Central Register of Controlled Trials (Issue 1, 2003), MEDLINE (1966 to 2003/03), EMBASE (1980 to 2003/03), manual searches of bibliographies and journals, authors of trials, and pharmaceutical companies.

SELECTION CRITERIA

Randomised trials comparing lactulose or lactitol versus no intervention, placebo, or antibiotics and trials comparing lactulose versus lactitol for hepatic encephalopathy.

DATA COLLECTION AND ANALYSIS

The primary outcome measures included no improvement of hepatic encephalopathy and all-cause mortality. Binary outcomes are reported as relative risks (RR) based on a random effects model. Subgroup analyses were performed with regard to methodological quality and form of hepatic encephalopathy.

MAIN RESULTS

Thirty trials assessed nonabsorbable disaccharides versus placebo, no intervention, or antibiotics or assessed lactulose versus lactitol. We could not extract data from all trials. Compared with placebo or no intervention, nonabsorbable disaccharides had no statistically significant effect on mortality (RR 0.41, 95% CI 0.02 to 8.68, four trials), but appeared to reduce the risk of no improvement of hepatic encephalopathy (RR 0.62, 95% CI 0.46 to 0.84, six trials). However, this result may reflect bias due to low methodological quality of the majority of included trials. Trials of high methodological quality found no significant effect of nonabsorbable disaccharides on the risk of no improvement (RR 0.92, 95% CI 0.42 to 2.04, two trials). We found no statistically significant difference between lactulose and lactitol on mortality (two trials) or risk of no improvement (four trials). However, our meta-analyses were underpowered to establish whether these treatments have comparable effect. Nonabsorbable disaccharides appeared to be inferior to antibiotics on reducing the risk of no improvement (RR 1.24, 95% CI 1.02 to 1.50, 10 trials).

REVIEWERS' CONCLUSIONS

This systematic review questions the beneficial effects of nonabsorbable disaccharides and highlights that there is insufficient high-quality evidence to support this treatment. We found that antibiotics appeared to be superior to nonabsorbable disaccharides in improving hepatic encephalopathy, but it is unclear whether this difference in treatment effect is clinically important to patients. Nonabsorbable disaccharides should not serve as comparator in randomised trials on hepatic encephalopathy.

Pharmacokinetics and anti-hyperglycaemic efficacy of a novel inhibitor of glycogen phosphorylase, 1,4-dideoxy-1,4-imino-d- arabinitol, in glucagon-challenged rats and dogs and in diabetic ob/ob mice

AIM

To further characterize the properties of 1,4-dideoxy-1,4-imino-d-arabinitol (DAB), a recently described novel and potent inhibitor of glycogen phosphorylase and potential anti-diabetic agent, we have determined its pharmacokinetic properties in rats, dogs and mice and compared these to its pharmacodynamic anti-hyperglycaemic efficacy.

METHODS

Male Sprague Dawley rats, beagle dogs and diabetic Umeå ob/ob mice were administered DAB or 14C-DAB at various doses and by different routes and in either the conscious or the unconscious state and with or without glucagon, as appropriate. At different time points thereafter, blood, tissue and urine samples were withdrawn for analyses of DAB or 14C-DAB, and blood samples were taken for glucose concentration.

RESULTS

DAB suppressed the blood glucose excursion in glucagon-challenged rats with an ID100 of 1-2 mg/kg per orally and intravenously and had a pharmacodynamic t50 for 1.6 mg/kg intravenously and for 1.2 mg/kg per orally of 50 and 60 min respectively. The pharmacokinetics of c. 2 mg/kg DAB in rats revealed elimination half-lives of 25 min after intravenous (i.v.) and 49 min after per oral (p.o.) administration; the oral bioavailability was 89%. In rats, DAB was distributed preferentially in liver vs. skeletal muscle and was eliminated predominantly through urine as parent compound. The pharmacokinetics of 4 mg/kg DAB in dogs showed elimination half-lives of 107 min after i.v. and 129 min after p.o. administration with an estimated oral availability of 78%. At 4 mg/kg DAB p.o., glucagon-induced hyperglycaemia in dogs was reduced in a time-dependent manner with an estimated t50 of 4 h. DAB was very rapidly cleared in mice; nevertheless, a dose-dependent reduction of blood glucose of up to 9 mmol/l was seen in diabetic ob/ob mice dosed subcutaneously, with statistically significant effects evident from 30 to 120 min.

CONCLUSIONS

These data show that DAB is nearly completely orally available in rats and dogs and that it can reduce glucagon-induced and spontaneous hyperglycaemia. Inhibition of hepatic glycogen phosphorylase may benefit glycaemic control in patients with type 2 diabetes.

Effects of lactulose and lactitol on coliform bacteria and bacterial translocation in the caecum during 72-h starvation in rats

Lactulose and lactitol, non-absorbable disaccharides, prevent bacterial translocation (BT) arising from the gut. In contrast, lack of food into the gut leads to coliform bacterial overgrowth and even if it does not cause BT, can induce the risk from other stimuli for BT. In this study, we tested whether lactulose and lactitol affected populations of coliform bacteria in the caecum during starvation in Sprague-Dawley rats. Three groups of rats were starved for 72 h and given oral 2 ml undiluted lactulose (670 mg/ml), 2 ml undiluted lactitol (666 mg/ml) or 2 ml physiological saline, respectively, once a day. The caecum and mesenteric lymph nodes (MLNs) were removed for microbiological and histopathological analyses. The highest degree of coliform bacterial overgrowth, BT to MLNs and histopathological damage were observed in lactulose-treated rats, followed by the group treated with lactitol. As a result of this study, both drugs, especially lactulose augmented the proliferation and translocation tendency of coliform bacteria in the caecum during 72-h starvation in rats.

Comparison of rifaximin and lactitol in the treatment of acute hepatic encephalopathy: results of a randomized, double-blind, double-dummy, controlled clinical trial

BACKGROUND/AIMS

The efficacy and safety of rifaximin in comparison with lactitol in the treatment of acute hepatic encephalopathy was assessed in a prospective randomized, double-blind, double-dummy, controlled trial.

METHODS

A total of 103 patients with grade I-III acute hepatic encephalopathy were randomized to receive rifaximin (50 patients, 1200 mg/day) or lactitol (53 patients, 60 g/day) for 5-10 days. Changes in the portal-systemic encephalopathy (PSE) index on entry and at the end of the study were used to evaluate the efficacy of the two therapies.

RESULTS

Both groups were comparable before treatment with regard to demographic data and characteristics of the hepatic encephalopathy episode. The global efficacy of both therapies was similar: 81.6% in the rifaximin group and 80.4% in the lactitol group showed improvement or total regression of the episode. A significantly better evolution of the PSE index was observed in the rifaximin group, due to a greater effect of rifaximin in two components of the index: EEG abnormalities and ammonia levels. No serious adverse events related to either treatment were found during the study.

CONCLUSIONS

Rifaximin may be considered a useful and safe alternative therapy to lactitol in the treatment of acute hepatic encephalopathy in cirrhosis.

The effect of polyol-combinant saliva stimulants on S. mutans levels in plaque and saliva of patients with mental retardation

The effect of chewable saliva-stimulants on Streptococcus mutans levels in dental plaque and paraffin-stimulated whole saliva among participants who were mentally disabled was investigated. Over 64-days, 98 participants chewed one of four saliva-stimulating tablets five times/day. The tablets contained one of the following: xylitol (X) or sorbitol (S), or 1:1 mixtures of xylitol and erythritol (XE) or sorbitol and erythritol (SE). Consumption of xylitol and sorbitol in Groups X and S was 5.4 grams/day/ subject, and of each polyol in Groups XE and SE, consumption was 2.7 g/day/subject. Interproximal dental plaque and stimulated whole saliva were sampled at baseline, at Day 36, and Day 64. There was a statistically significant reduction of S. mutans in plaque and saliva counts in Groups X and XE. The percentage of S. mutans in total streptococci increased significantly in dental plaque in Group S but decreased in the other groups. The results suggest that xylitol-containing saliva stimulants may be more effective than sorbitol-containing products in controlling some caries-associated parameters in people who are mentally disabled. Also a relationship may exist between the pentitol-type xylitol and S. mutans, and erythritol may exert a specific biochemical effect on this organism, although further studies are needed.

Caries preventive effect of sugar-substituted chewing gum

OBJECTIVES

The aim of this 3-year community intervention trial was to determine the caries preventive effect of sugar-substituted chewing gum among Lithuanian school children, and to assess compliance with the instructions for gum use.

METHODS

A total of 602 children, aged 9-14 years, from 28 school classes in five secondary schools in Kaunas, Lithuania, were given a baseline clinical and radiographic caries examination. The schools were randomly allocated to receive one of the following interventions: sorbitol/carbamide gum; sorbitol gum; xylitol gum; control gum; and no gum. Children in the four active intervention groups were asked to chew at least five pieces of gum per day, preferably after meals. The children were reexamined clinically after 1, 2 and 3 years, and radiographically after 3 years. Self-reported compliance was monitored anonymously four times during the study.

RESULTS

A total of 432 children were available at the 3-year clinical follow-up examination. The crude mean 3-year caries increments (DMFS--all stages of lesion formation) were 11.8 for the sorbitol/carbamide gum group; 9.0 for the sorbitol gum group; 8.1 for the xylitol gum group; 8.3 for the control gum group; and 12.4 for the no gum group. The adjusted 3-year caries increments were statistically significantly lower in the sorbitol gum group, the xylitol gum group and the control gum group than in the no gum group, whereas no statistically significant difference was seen between the no gum group and the sorbitol/carbamide gum group. Adjusted 3-year caries increments in the xylitol gum group and the sorbitol gum group did not differ statistically significantly from the caries increments in the control gum group. Compliance with the study protocol was better in School C (xylitol gum) than in the other schools. In all schools, compliance decreased over time.

CONCLUSION

The results indicate that the caries preventive effect of chewing sugar-free gum is related to the chewing process itself rather than being an effect of gum sweeteners or additives, such as polyols and carbamide.

Synthesis of nitrogen analogues of salacinol and their evaluation as glycosidase inhibitors

The syntheses of two nitrogen analogues (11 and 12) of the naturally occurring sulfonium ion, salacinol (7) are described. The latter compound is one of the active principles in the aqueous extracts of Salacia reticulata that are traditionally used in Sri Lanka and India for the treatment of diabetes. The synthetic strategy relies on the nucleophilic attack of a 1,4-dideoxy-1,4-imino-D- or L-arabinitol at the least hindered carbon of 2,4-O-benzylidene D- or L-erythritol-1,3-cyclic sulfate. The nitrogen analogues bear a permanent positive charge and serve as mimics of the sulfonium ion. We reasoned that these ammonium derivatives should function in a manner similar to that of known glycosidase inhibitors of the alkaloid class such as castanospermine (4) and deoxynojirimycin (5). Enzyme inhibition assays indicate that salacinol (7) is a weak (K(i) = 1.7 mM) inhibitor of glucoamylase, whereas compounds 11 and 12 inhibit glucoamylase with K(i) values in the range approximately 10-fold higher. The nitrogen analogues 11 and 12 showed no significant inhibitory effect of either barley alpha-amylase (AMY1) or porcine pancreatic alpha-amylase (PPA) at concentrations of 5 mM. In contrast, salacinol (7) inhibited AMY1 and PPA in the micromolar range, with K(i) values of 15 +/- 1 and 10 +/- 2 microM, respectively.

Effect of lactitol on blood ammonia response to oral glutamine challenge in cirrhotic patients: evidence for an effect of nonabsorbable disaccharides on small intestine ammonia generation

OBJECTIVE

Nonabsorbable disaccharides are widely used to decrease blood ammonia concentration. Their principal mode of action is the modification of pH and bacterial flora in the colon. The aim of the present study was to test the hypothesis that these drugs may also reduce small intestine ammonia generation.

METHODS

Eight male cirrhotics without overt hepatic encephalopathy received 20 g of glutamine in 100 ml of water. Venous samples for whole blood ammonia were taken before, 30 and 60 min after the load. Immediately after the last blood sample the patients were submitted to the following psychometric tests: number connection test, Posner's attention test, and Sternberg paradigm. After the first glutamine load, patients were started on lactitol (initial dose 20 g, three times a day). Once two bowel movements/day were obtained and maintained for at least 5 days, oral glutamine challenge and psychometric tests were repeated.

RESULTS

Ammonia increased significantly after the glutamine load (from 83 +/- 13 to 164 +/- 30 microg/dl at 30 min and 210 +/- 29 microg/dl at 60 min; mean +/- SE; p = 0.006 analysis of variance) but not after glutamine load after lactitol treatment (from 77 +/- 17 to 111 +/- 21 microg/dl and 142 +/- 24 microg/dl; p = not significant). The peak increment (127 +/- 24 vs 65 +/- 18 microg/dl; p = 0.008) of ammonia elevation was significantly smaller during lactitol administration. The patients' psychometric performance after the glutamine load did not differ significantly after lactitol treatment.

CONCLUSIONS

Lactitol reduces the elevation in blood ammonia that follows oral glutamine challenge. Because enterally administered glutamine is efficiently absorbed in the jejunum and, in part, metabolized to ammonia we suggest that lactitol affects small intestine ammonia generation probably by shortening the residence time of intestinal contents.

Comparison between saliva stimulants and a saliva substitute in patients with xerostomia and hyposalivation

The purpose of this study was to assess patient preference and product efficacy of three non-prescription products for the symptomatic relief of xerostomia. The study group consisted of 80 individuals with a complaint of chronic (> six months) xerostomia and an unstimulated salivary flow rate of < 0.1 mL/min. The three products--a sorbitol/xylitol-sweetened chewing gum, a sorbitol-sweetened sour lemon lozenge, and a sorbitol/xylitol-sweetened artificial saliva substitute spray--were assigned in a permuted block randomization scheme. Each product was used for two weeks with an interval of one week between trials. The study did not identify any product to be statistically significant in terms of patient preference. Kruskal-Wallis testing revealed no statistical significance (P > 0.589) among the products. No product demonstrated marked efficacy in stimulating salivary output. ANOVA analysis followed by Tukey HSD testing revealed no significant difference between the baseline paraffin-stimulated mean flow rate and the gum- and lozenge-stimulated flow rates.

Faecal steroids and colorectal carcinogenesis

BACKGROUND

Colorectal cancer is a major disease of Western civilizations and diet may account for approximately 35% of cases. Epidemiologic studies reveal that the major dietary constituents implicated in the disease process are fat/red meat (causative) and fibre (protective). From this standpoint, toxicologists have evaluated a plethora of dietary and intestinal biochemical characteristics and steroids; the bile acids especially have received a great deal of attention. Formerly, bile acids and their bacterial metabolites were implicated, as either mutagens and/or carcinogens, but this was not proven. In recent times, based mainly on animal model systems, opinion favours that if bile acids and their metabolites have a role to play in colon carcinogenesis, they act at the promotion stages of the adenoma-carcinoma sequence-the secondary bile acids deoxycholic and lithocholic acids being of major importance here. From this standpoint, studies have been designed either to lower total bile acid concentration or at least to reduce dehydroxylation of the primary bile acids via high fibre dietary regimes.

METHODS AND RESULTS

The prebiotics lactulose and lactitol (non-digestible dietary fibres) appear to have potential here, and so the effect of lactulose on fermentation by intestinal bacteria in a continuous culture model of the human colon was studied. Lactulose reduced dehydroxylation of chenodeoxycholic acid to the potentially toxic secondary bile acid lithocholic by over 90%. By contrast, lactitol, a reduced equivalent of lactulose, had little effect on 7 alpha-dehydroxylation of primary bile acids in the rectosigmoid colon of the miniature pig and in human faeces, but caused a significant decrease in steroid concentration, especially bile acids in human faeces.

CONCLUSIONS

If secondary steroid metabolites have a role to play in colorectal carcinogenesis, then dietary supplementation with prebiotics may be ameliorative in high-risk groups.

[Study of early postoperative lactitol versus paraffin following anal surgery in 110 adult patients]

The aim of this open and randomised clinical trial was to compare, in terms of efficacy, lactitol with petroleum jelly, regarding the time before recovery of intestinal transit in patients having undergone anal surgery. Efficacy, comfort and tolerability were assessed on day 4 and 7, the convenience of treatments at the end of the period. The main criterion for efficacy was the time taken to obtain the first stool after surgery. Lactitol appears to be more effective than petroleum in terms of recovery of intestinal transit: the first postoperative stool was obtained 13 hours earlier with lactitol. This difference is statistically significant whatever the comparison: survival analysis (p = 0.0018) or t test on means (p = 0.0014). The secondary criteria for efficacy are consistent with this first result: the mean number of stools per day was significantly higher with lactitol (p = 0.046), the daily dose could be-reduced for more patients under lactitol on day 4 (p = 0.004) and, also on day 4, the general efficacy assessment was significantly in favour of lactitol (p = 0.033). The separate analysis of the items included in the comfort score shows that stools are more often "normal or soft" in the petroleum group and that pain on defecation is frequently less severe in the lactitol group. This led to a significantly higher comfort score in the petroleum group from D1 to D4 but not from D1 to D7. Tolerance was rated "good" by 97% of patients on day 7, and no statistically significant difference was observed for any of the tolerability criteria. Lactitol therefore appears to be an interesting choice, with a high benefit/risk ratio, in the treatment of the transitory constipation frequently observed immediately after anal surgery.

Xylitol chewing gums and caries rates: a 40-month cohort study

Dental caries is a pandemic infectious disease which can affect the quality of life and consumes considerable health care resources. The chewing of xylitol, sorbitol, and even sugar gum has been suggested to reduce caries rates. No clinical study has simultaneously investigated the effectiveness of these gums when compared with a group receiving no chewing gum. A 40-month double-blind cohort study on the relationship between the use of chewing gum and dental caries was performed in 1989-1993 in Belize, Central America. One thousand two hundred and seventy-seven subjects (mean age, 10.2 years) were assigned to nine treatment groups: one control group (no supervised gum use), four xylitol groups (range of supervised xylitol consumption: 4.3 to 9.0 g/day), two xylitol-sorbitol groups (range of supervised consumption of total polyols: 8.0 to 9.7 g/day), one sorbitol group (supervised consumption: 9.0 g/day). The gum use during school hours was supervised. Four calibrated dentists performed the caries registrations by means of a modified WHO procedure. The primary endpoint was the development of an unequivocal caries lesion on a non-cavitated tooth surface. Compared with the no-gum group, sucrose gum usage resulted in a marginal increase in the caries rate (relative risk, 1.20; 95% confidence interval,0.96 to 1.49; p = 0.1128). Sorbitol gum significantly reduced caries rates (relative risk 0.74; 95% confidence interval, 0.6 to 0.92 ; p = 0.0074). The four xylitol gums were most effective in reducing caries rates, the most effective agent being a 100% xylitol pellet gum (relative risk, 0.27; 95% confidence interval, 0.20 to 0.36; p = 0.0001). This gum was superior to any other gum (p < 0.01). The xylitol-sorbitol mixtures were less effective than xylitol, but they reduced caries rates significantly compared with the no-gum group. DMFS analyses were consistent with these conclusions. The results suggest that systematic usage of polyol-based chewing gums reduces caries rates in young subjects, with xylitol gums being more effective than sorbitol gums.

Effects of lactitol [correction of lactilol] on hepatic encephalopathy and plasma amino-acid imbalance

Hepatic encephalopathy in liver cirrhosis is due to several factors, including amino acid imbalance and hyperammonemia. Lactitol [correction of lactilol], a non adsorbable disaccharide, improves hepatic encephalopathy increasing bowel movements, modifying colonic bacteria and pH, and reducing blood ammonium. Ten patients with liver cirrhosis and longstanding stable hepatic encephalopathy were treated, after a period of drugs wash-out, with lactitol. A significant improvement of hepatic encephalopathy was observed, with a significant decrease of blood ammonium, related with the increase of stool frequency/day. Atrial natriuretic peptide decreased as well. Moreover, an increase of the ratio of plasma aliphatic amino acids (valine, leucine and isoleucine)/aromatic amino acid (tyrosine and phenylalanine) was observed. Lactitol is an effective drug in the treatment of chronic hepatic encephalopathy; its mechanism of action involves not only a decrease of blood ammonium but also modifications of the degree of plasma amino acid imbalance, and fluid and circulatory adjustments.

[The effect of lactitol (NS-4) on the concentrations of ammonia and amino acids in blood and cerebrospinal fluid in Eck fistula (portacaval-shunted) dogs]

Lactitol and lactulose were compared in their effect on the concentrations of ammonia and amino acids in blood and cerebrospinal fluid (CSF) in Eck fistula dogs. Drugs were administered intragastrically for four weeks from three weeks after the portacaval-shunt operation. The concentration of ammonia in the blood and CSF had increased three- to five-fold three weeks after the operation and increased gradually thereafter. Eck fistula dogs showed a characteristic profile of plasma amino acids, with increased concentrations of tryptophan (Trp) and aromatic amino acids (AAA) and reduced concentrations of branched-chain amino acids. The profile of CSF amino acids revealed substantial increases in the concentrations of AAA as well as glutamine (Gln), Trp and glutamic acid. Lactitol at doses of 1 and 3 g/kg/day significantly decreased the ammonia concentration in both the blood and CSF after administration for two and four weeks. Lactitol at a dose of 3 g/kg/day significantly decreased the concentration of Trp in the plasma and the concentrations of valine, leucine, AAA and Gln in CSF. Lactulose showed effects similar to those of lactitol. These findings suggest that lactitol may be a promising agent for the clinical treatment of hyperammonemia and hepatic encephalopathy, since it decreased the concentration of ammonia in the blood and CSF and the elevated concentrations of AAA in CSF associated with the development of hepatic encephalopathy.

[Lactitol in chronic idiopathic constipation in children]

Fifty-one children affected by chronic idiopathic constipation (23 males, 28 females), ranging in age from 8 months to 16 years were enrolled in the study; 42 completed the trial. The patients were divided into two groups: Group A: 19 children treated with lactitol (250-400 mg/kg/day); Group B:23 patients treated with lactulose (500-750 mg/kg/day). Parents filled a questionnaire concerning clinical response to therapy for a period of 30 days. In 17 Group A children and in 17 Group B children orocecal transit time using H2 Breath Test with lactulose was performed. A statistically significant increase of week stool frequency was found after treatment both with lactitol or lactulose (p < 0.001). Nevertheless Group B patients complained abdominal pain (p < 0.005) and flatus (p < 0.001) more frequently. Other adverse reactions, such as vomiting and meteorism, were more frequent in Group B patients (n.s.). In addition patients treated with lactitol found that sugar as more palatable and had a better compliance to the therapy. Orocecal transit time did not show statistically significant differences after the therapy with both these sugars, indicating that the activity of lactulose and lactitol occurs in the colon and that small bowel functions are not affected by a previous therapy with these sugars. In conclusion, our study demonstrate that lactitol, because of the less number of side effects compared to lactulose, should be considered as an useful agent in the treatment of chronic idiopathic constipation in childhood.

Effect of polyol gums on dental plaque in orthodontic patients

Sixty 11- to 15-year-old children wearing fixed orthodontic appliances were given chewing gums containing polyol for daily use after meals and snacks, to study whether the chewing of gums that contained slowly fermentable polyols (xylitol and sorbitol) affects the amount of dental plaque and the number of mutans streptococci present in plaque and saliva. The 60 subjects were randomly divided into four groups, each of which was provided with a supply of 1.35 gm pellet-shaped gums for a period of 1 month, as follows: (1) xylitol; (2) sorbitol; (3) xylitol-sorbitol mixture I (3:2); and (4) xylitol-sorbitol mixture II (4:1). In each group, two pellets with a total initial gum mass of 2.7 gm (maximum polyol dose per day: 10.5 gm), were used six times a day. The fresh and dry weight of dental plaque, collected at baseline and 28 days later from incisors, canines, and premolars from the area between gingival margin and the bracket, reduced in all groups, but most significantly (by 43% to 47%) in children receiving xylitol gum. The plaque and saliva levels of mutans streptococci did not change in the sorbitol group, but was significantly (in most cases) reduced by 13% to 33% in groups that received gum containing xylitol. Provided that the quantity of dental plaque and the plaque and salivary levels of mutans streptococci can be regarded as risk factors in dental caries, these results suggest that regular use of polyol gum--and especially gum that contains xylitol as the predominant sweetener--can reduce the caries risk in young patients wearing fixed orthodontic appliances.

[Ameliorating effect of lactitol on experimental hepatic encephalopathy in Eck fistula dogs]

Eck fistula (portacaval shunted) dogs were prepared for use as an experimental model of chronic hepatic encephalopathy. The effect of lactitol on hepatic encephalopathy was investigated by observing the behavior, electroencephalograms (EEGs) and visually evoked potentials (VEPs) of the experimental dogs. Lactitol was administered intragastrically once a day for 12 weeks from the third week after the portacaval-shunt operation and the behavior, EEGs and VEPs of the dogs were observed every two weeks. Dogs not given lactitol became sluggish, then apparently blind, and eventually fell into a coma, over a period of several weeks after the operation. Some dogs died. The EEGs revealed low-voltage slow waves and, at a later stage, displayed flattening in some dogs. The VEPs displayed prolonged latency of both the positive and the negative component as well as an increased amplitude. Lactitol at 1 or 3 g/kg/day suppressed the behavioral symptoms and the changes in the EEGs and the VEPs. These results suggest that lactitol may be useful for the treatment of various nervous symptoms in patients with hepatic encephalopathy accompanied by hyperammonemia.

Stabilisation of rampant caries: polyol gums and arrest of dentine caries in two long-term cohort studies in young subjects

The purpose of this paper is to report clinical observations on the stabilisation of dentine caries in two chewing gum studies carried out in young subjects. One study focused on the permanent dentition of 1,277 initially 10-year old subjects, while the other study was carried out on 510 initially 6-year old subjects and focused on the primary dentition. In both trials, several chewing gum formulas containing dietary polyols (xylitol and sorbitol, or their combinations) were used for up to 40 months (10-year olds) or up to 24 months (6-year olds). The daily consumption level of both polyols was up to 10.7 g per subject, used normally in 5-minute chewing episodes 3 to 5 times per day. Supervised chewing in schools lasted 5 min per episode, and for variable times during non-school days. Rehardening of dentine caries lesions was observed clinically by experienced, blinded examiners using sharp dental explorers and fibre optic light. After 40 months (permanent dentition) or after 18 months (primary dentition), rehardening (caries arrest) generally occurred more frequently in subjects who used polyol gums than in subjects who did not receive gum as part of the programmes, or who received sucrose gum. Arrest or non-progression of dentine caries was most frequently observed in subjects who used 100 per cent xylitol gums or mixtures of xylitol and sorbitol, but the differences between gums were not consistently significant. However, the usage of 100 per cent xylitol pellet-shaped gum was more frequently associated with arrest of dentine caries than other treatments. These results and previous studies suggest that high-xylitol chewing gum usage can retard or arrest even rampant dentine caries in conditions where effective restoration and prevention programmes have not been instituted, and can also provide additional protection against further caries development during full implementation of restorative procedures by holding the lesion in a non-progressive condition.

Prevention of bovine ketosis with glucogenic substance and its effect on fertility in Finnish dairy cows

To avoid a harmful peak of negative energy balance, 200 ml of a 50% propylene glycol and 1% nicotinic amide solution were given twice a day to dairy cattle for ten days starting at day 14 post partum (p.p). Acetone content in milk was used as an indicator of energy balance and fertility was used as an indicator of the efficiency of the treatment. In addition, other factors affecting fertility were evaluated. During the prevention period, the acetone level in the prevention group (N = 31) decreased from 0.40 +/- 0.1 O mmol/l to 0.23 +/- 0.06 mmol/l (p = 0.09), but in the control group (N = 35) it increased from 0.23 +/- 0.04 mmol/l to 0.43 +/- 0.29 mmol/l acetone from the beginning to the end of the trial (p > 0.10). At day 50 p.p., however, the acetone levels in the two groups were the same. The treatment did not prevent clinical ketosis. Clinical ketosis tended to be associated with impaired fertility; in contrast, cows in the prevention group treated for ketosis had high fertility. A high daily milk yield at the first monthly recording test as well as high annual milk, fat and protein yields were correlated with the interval from calving to conception, r = 0.33, r = 0.50, r = 0.37 and r = 0.47, respectively. A low percentage of annual milk protein and at test 1 was significantly correlated with a long interval from calving to conception, r=-0.31 and r=-0.45, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of porto-systemic encephalopathy with lactitol verus lactulose: a randomized controlled study

BACKGROUND

Lactitol (beta-galactosido-sorbitol), a novel disaccharide analogue of lactulose, has been suggested as an alternative to lactulose in the treatment of portosystemic encephalopathy (PSE) in Western country. In order to assess its therapeutic effect and adverse reaction in PSE in the Chinese, we conducted this study.

METHODS

Forty-one patients with PSE were enrolled in this study. Patients were randomly divided into 2 groups to receive lactitol (n = 21) or lactulose (n = 20) for 5 days. The doses of both drugs were adjusted to keep daily bowel movement of 2 to 3 times. The PSE index (mental state, EEG, asterixis, number connection test [NCT], and ammonia) was evaluated in each patient before and after treatment. Daily doses of lactitol and lactulose, stool frequency, and side effect were recorded.

RESULTS

The mean dose of lactitol used was 66.3 +/- 36.4 gm and that of lactulose was 56.9 +/- 32.1 ml of lactulose. The majority of patients (37/41) gained clear consciousness after 5 days' treatment. In the lactitol group, blood ammonia, EEG, NCT, asterixis, mental status and PSE index before treatment were 208 +/- 62 micrograms/ml, 2.9 +/- 0.8, 4.0 +/- 0.0, 2.7 +/- 1.5, 2.9 +/- 0.7 and 77.1 +/- 10.5, respectively. All parameters decreased significantly after 5 days' treatment (119 +/- 50 micrograms/ml, 1.1 +/- 1.0, 2.9 +/- 1.2, 1.7 +/- 1.1, 0.7 +/- 0.7, and 34.4 +/- 16.0, p < 0.05). The lactulose group had the similar results. However, the improvement of PSE index after therapy in the lactitol group was significantly higher than that in the lactulose group (42.7 +/- 19.3 vs 31.1 +/- 13.7, p < 0.05). In addition, more patients in the lactitol group than in the lactulose group (67% vs 20%, p = 0.003) favored the taste of their assigned drugs. No patient who received lactitol experienced any side effects; however, six patients treated with lactulose complained of meteorism and flatulence, and four complained of nausea.

CONCLUSIONS

Both lactitol and lactulose are effective in the treatment of PSE, though the effect of lactitol seems slightly superior to that of lactulose in our study. Lactitol is more acceptable to our patients due to better palatability and less side effects. Lactitol is another good alternative in the treatment of PSE.

Effects of long-term administration of low-dose lactitol in patients with cirrhosis but without overt encephalopathy

To investigate the efficacy and the acceptability of different doses of lactitol in patients with subclinical hepatic encephalopathy, 28 patients with cirrhosis were enrolled in a controlled clinical trial comparing 5-month therapies with lactitol at two different doses: 0.3 and 0.5 g/kg bw per day. This period was followed by 1 month of recovery. Patients were monitored with venous blood ammonia determination, three psychometric tests, clinical evaluation of mental status and EEG. The porto-systemic encephalopathy index of Conn was determined periodically. Twenty-two patients completed the trial (11 for each dose of lactitol). Both doses of lactitol decreased plasma ammonia levels and improved the porto-systemic encephalopathy index. The higher dose was more effective in improving performance in the psychometric tests. After the period of recovery, both the porto-systemic encephalopathy index and the psychometric test scores returned to pretreatment values. Lactitol was tolerated well by patients. Three patients given the higher dose reported periodic intestinal discomfort, but did not stop taking lactitol or reduce the dosage; no side-effects were reported by the patients taking the lower dose. These results indicate that lactitol in doses ranging from 0.3 to 0.5 g/kg bw is a well-tolerated and effective treatment for subclinical encephalopathy.

[Lactulose and its derivatives--treatment of hepatic encephalopathy and other possible indications for its use]

Lactulose and lactitol, the synthetic compounds of lactose, are poorly absorbed from the small intestine, and both are almost exclusively metabolized by the bacterial flora of the colon. These disaccharides shorten the small bowel transit time mechanically and lower the pH of the bowel, both by their osmotic effects and by the acidic pH of their metabolites. Lactulose and lactitol diminish the absorption of ammonia and metabolites of other toxic proteins by two distinct mechanisms; by exerting a cathartic effect and by suppressing the dissociation of ammonia. Lactulose and lactitol are the classical therapy of choice for the treatment of hepatic encephalopathy since 1964 and since 1982, respectively. Another indication is, the treatment of constipation. Because lactulose decreases the concentration of cholic acid and may prevent its absorption, the drug was recently suggested to be successful for the prevention of recurrence of cholesterol stone formation, and to be useful as an anticarcinogenic agent.

Lactitol in treatment of chronic hepatic encephalopathy. A meta-analysis

The efficacy and side effects of lactitol in the treatment of chronic hepatic encephalopathy was compared to that of other disaccharides in a meta-analysis of published randomized clinical trials (RCTs). The outcomes assessed were: (1) the rate of patients free from episodes of clinically detectable encephalopathy, and (2) the rate of patients free from one or more side effects in the different treatment groups. Four RCTs were eligible for analysis; in three lactitol was compared to lactulose, in one the alternative treatment was lactose in lactase-deficient patients. The methodological quality of these studies was high. Meta-analysis showed that lactitol was as effective as other disaccharides in the treatment of encephalopathy: pooled odds ratio was 0.83, 95% confidence interval was 0.38-1.82. Results were not sensitive to the use of alternative methods of counting and attributing events in these trials. Patients experienced fewer side effects during treatment with lactitol, but the pooled odds ratio was not statistically significant. In all studies lactitol was considered more palatable. Clinical effectiveness of lactitol, in long-term treatment of chronic encephalopathy, is similar to those of lactulose. It seems that lactitol has lower side effects than lactulose. Future RCTs with a double-blind design could be mainly aimed at evaluating the side-effect profile of the two disaccharides.

Efficacy of sweeteners and sugar substitutes in caries prevention

The caries-preventive efficacy of sweeteners and sugar substitutes is not clearly established on an epidemiological scale. A review of cariogenicity assessments in vitro and in vivo as well as of human clinical caries trials, however, clearly demonstrates that the replacement of sugar by such products has a caries-preventive effect. The clinical relevance of some bacteriostatic and/or cariostatic properties ascribed to saccharin, aspartame, and xylitol remains to be corroborated.

The effect of lactulose and lactitol administration on fecal fat excretion in patients with liver cirrhosis

Mild to moderate fat malabsorption is frequently present in patients with liver cirrhosis. We investigated the influence of lactulose or lactitol treatment on fecal fat excretion in 18 patients with liver cirrhosis. All patients were Child Pugh class A or B and had not taken any therapy that could have affected intestinal absorption in the previous months. The dose of lactulose or lactitol was individually adjusted to maintain two semiliquid bowel movements per day. Steatorrhea was determined before and after a minimum of 7 days, when the cathartic effect was stabilized. Treatment with nonabsorbable disaccharides induced mild to moderate steatorrhea in 50% of patients. No differences were observed between the effects of lactulose and lactitol, but fecal fat excretion exceeded 10 g/day in two patients taking lactulose. These findings indicate that treatment with nonabsorbable disaccharides may increase fecal fat excretion in patients with liver cirrhosis. This factor should be taken into consideration when a cirrhotic patient has to take these drugs for a long time.