Antidiarrheal effects of L-histidine-supplemented rice-based oral rehydration solution in the treatment of male adults with severe cholera in Bangladesh: a double-blind, randomized trial

A double-blind clinical trial to compare the efficacy and safety of a multiple amino acid-based ORS with the standard WHO-ORS in the management of non-cholera acute watery diarrhea in infants and young children: "VS002A" trial protocol

BACKGROUND

Diarrhea is the second deadliest disease for under-five children globally and the situation is more serious in developing countries. Oral rehydration solution (ORS) is being used as a standard treatment for acute watery diarrhea for a long time. Our objective is to compare the efficacy of amino acid-based ORS "VS002A" compared to standard glucose-based WHO-ORS in infants and young children suffering from acute non-cholera watery diarrhea.

METHODS

It is a randomized, double-blind, two-cell clinical trial at Dhaka Hospital of icddr,b. A total of 312 male children aged 6-36 months old with acute non-bloody watery diarrhea are included in this study. Intervention arm participants get amino acid-based ORS (VS002A) and the control arm gets standard glucose-based WHO-ORS. The primary efficacy endpoint is the duration of diarrhea in the hospital.

DISCUSSION

Oral rehydration therapy (ORT) with the present ORS formulation has certain limitations - it does not reduce the volume, frequency, or duration of diarrhea. Additionally, the failure of present standard ORS to significantly reduce stool output likely contributes to the relatively limited use of ORS by mothers as they do not feel that ORS is helping their child recover from the episode of diarrhea. Certain neutral amino acids (e.g., glycine, L-alanine, L-glutamine) can enhance the absorption of sodium ions and water from the gut. By using this concept, a shelf-stable, sugar-free amino acid-based hydration medicinal food named 'VS002A' that effectively rehydrates, and improves the barrier function of the bowel following infections targeting the gastrointestinal tract has been developed. If the trial shows significant benefits of VS002A use, this may provide evidence to support consideration of the use of VS002A in the present WHO diarrhea management guidelines. Conversely, if there is no evidence of benefit, these results will reaffirm the current guidelines.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04677296 . Registered on December 21, 2020.

Carnosine and histidine-containing dipeptides improve dyslipidemia: a systematic review and meta-analysis of randomized controlled trials

CONTEXT

Cardiovascular disease is a major public health problem and represents a significant burden of disease globally. Lifestyle interventions have their limitations and an intervention that will effectively address cardiovascular risk factors to help reduce this growing burden of disease is required.

OBJECTIVE

Carnosine and other histidine-containing dipeptides (HCDs) have exerted positive effects on cardiovascular risk factors and diseases in animal and human studies. The authors conducted a systematic review and meta-analysis examining the effects of HCDs on cardiovascular outcomes in line with the PRISMA guidelines.

DATA SOURCES

The Medline, Medline in process, Embase, Cumulative Index of Nursing and Allied Health, and All EBM databases were searched from inception until January 25, 2019, for randomized controlled trials (RCTs) examining the effects of HCDs on cardiovascular outcomes, compared with placebo or controls.

DATA EXTRACTION

Basic characteristics of the study and populations, interventions, and study results were extracted. The grading of recommendations assessment, development, and evaluation approach was used to assess the quality of evidence for each outcome.

DATA ANALYSIS

A total of 21 studies were included. Of these, 18 were pooled for meta-analysis (n = 913). In low risk of bias studies, HCD-supplemented groups had lower total cholesterol (n = 6 RCTs; n = 401; weighted mean difference [WMD], -0.32 mmol/L [95%CI, -0.57 to -0.07], P = 0.01) and triglyceride levels (n = 6 RCTs; n = 401; WMD, -0.14 mmol/L [95%CI, -0.20 to -0.08], P < 0.001) compared with controls. In studies using carnosine, triglycerides levels were also lower in the intervention group vs controls (n = 5 RCTS; n = 309; P < 0.001). There were no significant differences in blood pressure, heart rate, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C) or the total cholesterol to HDL-C ratio between groups.

CONCLUSIONS

Carnosine and other HCDs may have a role in improving lipid profiles. Larger studies with sufficient follow-up are necessary to confirm these findings and explore the use of HCDs in the prevention of cardiovascular diseases.

SYSTEMIC REVIEW REGISTRATION

PROSPERO registration no.: CRD42017075354.

Treatment of severe cholera: a review of strategies to reduce stool output and volumes of rehydration fluid

Background

Severe cholera is a life-threatening illness of hypovolemic shock and metabolic acidosis due to rapid and profuse diarrheal fluid loss. Emergency life-saving therapy is i.v. saline, optionally supplemented with potassium and alkali to correct the fluid deficit, potassium losses and acidosis. After this initial rehydration, for the next 2 days ongoing stool losses are replaced with oral rehydration solution (ORS), which contains sodium chloride, potassium and alkali together with glucose or rice powder as a source of glucose to serve as a carrier for sodium.

Results

In actual field trials, antibiotics are given to reduce fluid requirements, but large volumes averaging about 7 liters of i.v. fluid followed by about 14 liters of ORS have been given to adult patients. Disturbing trends during therapy have included overhydration, hyponatremia and polyuria.

Conclusions

It is suggested that stool output and fluid requirements could be reduced, if borne out in future research, by avoiding overhydration by restricting ORS intake to match stool output and promoting intestinal reabsorption of luminal fluid by early introduction of glucose without salts into the intestine, more gradual correction of dehydration, giving mineralocorticoid and vasopressin, and infusing glucose or short-chain fatty acids into the proximal colon.

Rice Bran and Probiotics Alter the Porcine Large Intestine and Serum Metabolomes for Protection against Human Rotavirus Diarrhea

Human rotavirus (HRV) is a leading cause of severe childhood diarrhea, and there is limited vaccine efficacy in the developing world. Neonatal gnotobiotic pigs consuming a prophylactic synbiotic combination of probiotics and rice bran (Pro+RB) did not exhibit HRV diarrhea after challenge. Multiple immune, gut barrier protective, and anti-diarrheal mechanisms contributed to the prophylactic efficacy of Pro+RB when compared to probiotics (Pro) alone. In order to understand the molecular signature associated with diarrheal protection by Pro+RB, a global non-targeted metabolomics approach was applied to investigate the large intestinal contents and serum of neonatal gnotobiotic pigs. The ultra-high performance liquid chromatography-tandem mass spectrometry platform revealed significantly different metabolites (293 in LIC and 84 in serum) in the pigs fed Pro+RB compared to Pro, and many of these metabolites were lipids and amino acid/peptides. Lipid metabolites included 2-oleoylglycerol (increased 293.40-fold in LIC of Pro+RB, p = 3.04E-10), which can modulate gastric emptying, andhyodeoxycholate (decreased 0.054-fold in the LIC of Pro+RB, p = 0.0040) that can increase colonic mucus production to improve intestinal barrier function. Amino acid metabolites included cysteine (decreased 0.40-fold in LIC, p = 0.033, and 0.62-fold in serum, p = 0.014 of Pro+RB), which has been found to reduce inflammation, lower oxidative stress and modulate mucosal immunity, and histamine (decreased 0.18-fold in LIC, p = 0.00030, of Pro+RB and 1.57-fold in serum, p = 0.043), which modulates local and systemic inflammatory responses as well as influences the enteric nervous system. Alterations to entire LIC and serum metabolic pathways further contributed to the anti-diarrheal and anti-viral activities of Pro+RB such as sphingolipid, mono/diacylglycerol, fatty acid, secondary bile acid, and polyamine metabolism. Sphingolipid and long chain fatty acid profiles influenced the ability of HRV to both infect and replicate within cells, suggesting that Pro+RB created a protective lipid profile that interferes with HRV activity. Polyamines act on enterocyte calcium-sensing receptors to modulate intracellular calcium levels, and may directly interfere with rotavirus replication. These results support that multiple host and probiotic metabolic networks, notably those involving lipid and amino acid/peptide metabolism, are important mechanisms through which Pro+RB protected against HRV diarrhea in neonatal gnotobiotic pigs.

Polymer-based oral rehydration solution for treating acute watery diarrhoea

BACKGROUND

Acute diarrhoea is one of the main causes of morbidity and mortality among children in low-income countries. Glucose-based oral rehydration solution (ORS) helps replace fluid and prevent further dehydration from acute diarrhoea. Since 2004, the World Health Organization (WHO) has recommended the osmolarity of less than 270 mOsm/L (ORS ≤ 270) versus greater than 310 mOsm/L formulation (ORS ≥ 310). Polymer-based ORS (for example, prepared using rice or wheat) slowly releases glucose and may be superior to glucose-based ORS.

OBJECTIVES

To compare polymer-based oral rehydration solution (polymer-based ORS) with glucose-based oral rehydration solution (glucose-based ORS) for treating acute watery diarrhoea.

SEARCH METHODS

We searched the following sources up to 5 September 2016: the Cochrane Infectious Diseases Group (CIDG) Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 9), MEDLINE (1966 to 5 September 2016), EMBASE (1974 to 5 September 2016), LILACS (1982 to 5 September 2016), and mRCT (2007 to 5 September 2016). We also contacted researchers, organizations, and pharmaceutical companies, and searched reference lists.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of people with acute watery diarrhoea (cholera and non-cholera associated) that compared polymer-based and glucose-based ORS (with identical electrolyte contents).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the search results and risk of bias, and extracted data. In multiple-treatment arms with two or more treatment groups, we combined outcomes as appropriate and compared collectively with the control group.

MAIN RESULTS

Thirty-five trials that included 4284 participants met the inclusion criteria: 28 trials exclusively included children, five included adults, and two included both adults and children. Polymer-based ORS versus glucose-based ORS (osmolarity ≤ 270) Eight trials (752 participants) evaluated this comparison, and seven trials used rice as a polymer source. Polymer-based ORS may decrease mean stool output in the first 24 hours by 24 mL/kg (mean difference (MD) -24.60 mL/kg, 95% CI -40.69 to -8.51; one trial, 99 participants, low quality evidence). The average duration of diarrhoea may be reduced by eight hours (MD -8.24 hours, 95% CI -13.17 to -3.30; I² statistic = 86%, five trials, 364 participants, low quality evidence) with polymer ORS but results are heterogeneous. Limited trials showed no observed difference in the risk of unscheduled use of intravenous fluid (RR 0.66, 95% CI 0.43 to 1.02; I² statistic = 30%; four trials, 376 participants, very low quality evidence), vomiting (very low quality evidence), and hyponatraemia (very low quality evidence). Polymer-based ORS versus glucose-based ORS (osmolarity ≥ 310) Twenty-seven trials (3532 participants) evaluated this comparison using a variety of polymers. On average, polymer ORS may reduce the total stool output in the first 24 hours by around 65 mL/kg (MD -65.47 mL/kg, 95% CI -83.92 to -47.03; 16 trials, 1483 participants, low quality evidence), and may reduce the duration of diarrhoea by around eight hours (MD -8.57 hours; SD -13.17 to -4.03; 16 trials, 1137 participants, low quality evidence) with substantial heterogeneity. The proportion of participants that required intravenous hydration was low in most trials with fewer in the polymer ORS group (RR 0.75, 95% CI 0.57 to 0.98; 19 trials, 1877 participant, low quality evidence) . Subgroup analysis by type of pathogen suggested an effect on unscheduled intravenous fluid in those infected with mixed pathogens (RR 0.63, 95% CI 0.41 to 0.96; 11 trials, 928 participants, low quality evidence), but not in participants positive for Vibrio cholerae (RR 0.94, 95% CI 0.66 to 1.34; 7 trials, 535 participants, low quality evidence). No difference was observed in the number of patients who developed vomiting (RR 0.91, 95% CI 0.72 to 1.14; 10 trials, 584 participants, very low quality evidence), hyponatraemia (RR 1.82, 95% CI 0.52 to 6.44; 4 trials, 385 participants, very low quality evidence), hypokalaemia (RR 1.29, 95% CI 0.74 to 2.25; 2 trials, 260 participants, low quality evidence), or persistent diarrhoea (RR 1.28, 95% CI 0.68 to 2.41; 2 trials, 885 participants, very low quality evidence).

AUTHORS' CONCLUSIONS

Polymer-based ORS shows advantages compared to glucose-based ORS (at ≥ 310 mOsm/L). Comparisons favoured polymer-based ORS over ORS ≤ 270 but analysis was underpowered.

Histidine supplementation improves insulin resistance through suppressed inflammation in obese women with the metabolic syndrome: a randomised controlled trial

AIMS/HYPOTHESIS

Increased inflammation and oxidative stress are associated with insulin resistance (IR) and metabolic disorders. Serum histidine levels are lower and are negatively associated with inflammation and oxidative stress in obese women. The objective of this study was to evaluate the efficacy of histidine supplementation on IR, inflammation, oxidative stress and metabolic disorders in obese women with the metabolic syndrome (MetS).

METHODS

A total of 100 obese women aged 33-51 years with BMI ≥ 28 kg/m² and diagnosed with MetS were included following a health examination in the community hospital in this randomised, double-blinded, placebo-controlled trial. Participants were allocated to interventions by an investigator using sequentially numbered sealed envelopes and received 4 g/day histidine (n = 50) or identical placebo (n = 50) for 12 weeks. Participants then attended the same clinic every 2 weeks for scheduled interviews and to count tablets returned. Serum histidine, HOMA-IR, BMI, waist circumference, fat mass, serum NEFA, and variables connected to inflammation and oxidative stress were measured at baseline and 12 weeks. Participants, examining physicians and investigators assessing the outcomes were blinded to group assignment. In addition, the inflammatory mechanisms of histidine were also explored in adipocytes.

RESULTS

At 12 weeks, a total of 92 participants completed this trail. Compared with the placebo group (n = 47), histidine supplementation significantly decreased HOMA-IR (-1.09 [95% CI -1.49, -0.68]), BMI (-0.86 kg/m² [95% CI -1.55, -0.17]), waist circumference (-2.86 cm [95% CI -3.86, -1.86]), fat mass (-2.71 kg [95% CI -3.69, -1.73]), serum NEFA (-173.26 μmol/l [95% CI -208.57, -137.94]), serum inflammatory cytokines (TNF-α, -3.96 pg/ml [95% CI -5.29, -2.62]; IL-6, -2.15 pg/ml [95% CI -2.52, -1.78]), oxidative stress (superoxide dismutase, 17.84 U/ml [95% CI 15.03, 20.65]; glutathione peroxidase, 13.71 nmol/ml [95% CI 9.65, 17.78]) and increased serum histidine and adiponectin by 18.23 μmol/l [95% CI 11.74, 24.71] and 2.02 ng/ml [95% CI 0.60, 3.44] in histidine supplementation group (n = 45), respectively. There were significant correlations between changes in serum histidine and changes of IR and its risk factors. No side effects were observed during the intervention. In vitro study indicated that histidine suppresses IL6 and TNF mRNA expression and nuclear factor kappa-B (NF-κB) protein production in palmitic acid-induced adipocytes in a dose-dependent manner, and these changes were diminished by an inhibitor of NF-κB.

CONCLUSIONS/INTERPRETATION

Histidine supplementation could improve IR, reduce BMI, fat mass and NEFA and suppress inflammation and oxidative stress in obese women with MetS; histidine could improve IR through suppressed pro-inflammatory cytokine expression, possibly by the NF-κB pathway, in adipocytes.

Treatment of cholera-like diarrhoea with oral rehydration

Cholera diarrhoea remains a major global health problem that has caused seven pandemics. The pathogenesis of cholera is attributable to the production of cholera toxin by the causative pathogen, Vibrio cholerae. The toxin causes increased production of cyclic adenosine monophosphate and this results in massive water and electrolyte secretion into the intestinal lumen. These changes manifest clinically as the painless defecation of voluminous stools that resemble 'rice water', leading to severe dehydration. The cornerstone in the management of cholera diarrhoea is the use of oral rehydration solutions (ORS) to replace the water and electrolytes lost as stools. The World Health Organization recommends the use of ORS of 'reduced osmolarity' for the treatment of acute non-cholera diarrhoea and the use of rice-based ORS for the management of cholera diarrhoea. Although several attempts have been made to improve ORS, studies to evaluate some of the modifications, which include the addition of amylase-resistant starch, the use of amino acids (such as glycine, alanine and glutamine) as sodium cotransporters, and zinc-supplemented ORS, are still needed.

Polymer-based oral rehydration solution for treating acute watery diarrhoea

BACKGROUND

Acute diarrhoea is one of the principal causes of morbidity and mortality among children in low-income countries. Glucose-based ORS helps replace fluid and prevent further dehydration from acute diarrhoea. Since 2004, the World Health Organization has recommended the osmolarity < 270 mOsm/L (ORS </= 270 ) over the > 310 mOsm/L formulation (ORS >/= 310). Glucose polymer-based ORS (eg prepared using rice or wheat) slowly releases glucose and may be superior.

OBJECTIVES

To compare polymer-based ORS with glucose-based ORS for treating acute watery diarrhoea.

SEARCH STRATEGY

In September 2008, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2008, Issue 3), MEDLINE, EMBASE, LILACS, and mRCT. We also contacted researchers, organizations, and pharmaceutical companies, and searched reference lists.

SELECTION CRITERIA

Randomized controlled trials of people with acute watery diarrhoea (cholera and non-cholera associated) comparing polymer-based and glucose-based ORS (with identical electrolyte contents).

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the search results and risk of bias, and extracted data. In multiple treatment arms with two or more treatment groups, we combined outcomes as appropriate and compared collectively with the control group.

MAIN RESULTS

Thirty-four trials involving 4214 participants met the inclusion criteria: 27 in children, five in adults and two in both. Twelve trials used adequate methods to conceal allocation. Most compared polymer-based ORS with ORS >/= 310. There were fewer unscheduled intravenous infusions in the polymer-based ORS group compared with glucose-based ORS (ORS >/= 310 and </= 270 groups combined) (RR 0.75, 95% CI 0.59 to 0.95; 2235 participants, 19 trials). Adults positive for Vibrio cholerae had a shorter duration of diarrhoea with polymer-based ORS than with ORS </= 270 (MD -7.11 hours, SD -11.91 to -2.32; 228 participants, 4 trials). Wheat-based ORS resulted in lower total stool output in the first 24 hours compared with ORS </= 270 (MD -119.85 g/kg, SD -114.73 to -124.97; 129 participants, 2 trials). Adverse effects were similar for polymer-based ORS and glucose-based ORS.

AUTHORS' CONCLUSIONS

Polymer-based ORS shows some advantages compared to ORS >/= 310 for treating all-cause diarrhoea, and in diarrhoea caused by cholera. Comparisons favoured the polymer-based ORS over ORS </= 270, but the analysis was underpowered. If specialists consider a potential role for polymer-based ORS, further trials against the current standard (ORS </= 270) will be required.

Reducing renal uptake of111In-DOTATOC: A comparison among various basic amino acids

PURPOSE

Several studies have reported significant renal toxicity after the use of a high dose of 90Y-DOTATOC. Thus, renal protection is necessary in treatments with 90Y-DOTA Tyr3-octreotide (DOTATOC). The infusion of certain positively charged amino acids has been shown to effectively reduce renal uptake of DOTATOC. In this study, we compared the effectiveness of three kinds of amino acids, D-lysine (lysine), L-arginine (arginine) and histidine, on renal protection in healthy rats and tried to determine which one was the most effective.

METHODS

Twenty SD healthy male rats were divided into 4 groups: lysine, histidine, arginine, and control. The rats were injected with a dose of 400 mg/kg of amino acid or 2 ml of phosphate-buffered saline (PBS) (as control) intraperitoneally. All rats were sacrificed at 4 hrs after the injection of 1 MBq 111In-DOTATOC. Samples of the kidney were taken and weighed carefully. The counts of radioactivity were measured by a gamma counter and renal concentrations were calculated and expressed as percent injected dose per gram (% ID/g).

RESULTS

The renal uptake of 111In-DOTATOC was significantly lower for all three kinds of amino acids when compared to the control group. The renal uptake of 111In-DOTATOC in the lysine group was significantly lower than those in the histidine and arginine groups. The renal uptake of 111In-DOTATOC in the histidine group was lower than that in the arginine group, but no statistical difference was noted.

CONCLUSION

Among these three amino acids, lysine had the best reduction rate of renal uptake of DOTATOC. Histidine was more effective than arginine but no statistical difference was noted.