Early glucose and methylene blue are effective against unripe ackee apple (Blighia sapida) poisoning in mice

Acute encephalopathy in children in Muzaffarpur, India: a review of aetiopathogenesis

The acute encephalopathy occurring in children in Muzaffarpur, India, also recognised in other litchi-cultivating areas of India, Bangladesh, Vietnam and China, had previously been linked to litchi consumption. Recently, it has been identified as hypoglycaemic encephalopathy of an unusual aetiology with three key factors: undernutrition, prolonged fasting and litchi consumption. A second set of investigators has independently reconfirmed the diagnosis and the three-factor aetiology. Skipping the evening meal with an intake of large amounts of litchi in undernourished children is causative. Early-morning hypoglycaemia with an inadequate glycogen store leads to initiation of gluconeogenesis and fatty acid β-oxidation, but methylene cyclopropyl alanine and glycine present in the litchi aril block the fatty acid β-oxidation cycle. The outcomes are uncorrected hypoglycaemia and encephalopathy due to the entry of metabolic intermediates that cross the blood-brain barrier and affect neuronal function. Suggested measures include early 10% dextrose infusion. Awareness about the disease is of prime importance. The diagnosis and aetiopathogenesis are still under question from a part of the scientific community. This review was undertaken to present a comprehensive view of hypoglycaemic encephalopathy and to remove some of the lingering doubts.

Evaluation of neurotoxicity and hepatotoxicity effects of acute and sub-acute oral administration of unripe ackee (Blighia sapida) fruit extract

•

Acute oral dose of 2000 mg/kg of unripe B. sapida fruit extract (BSE) was toxic to mice.

•

Repeated treatment with BSE impaired locomotor function, memory performance and shortened seizure latency in mice.

•

Repeated treatment with BSE significantly up-regulate acetylcholinesterase enzyme activity in mice.

•

Repeated treatment with BSE elevates oxidative stress in the brain and liver of mice.

•

Repeated treatment with BSE showed histopathological evidences of toxicity in mice brain and liver.

Ackee (Blighia sapida) is a commonly eaten fruit that is indigenous to West Africa and Jamaica. Ackee poisoning in young children have been reported in parts of Nigeria due to consumption of the unripe fruits. This study was designed to identify potential mechanisms of acute and sub-acute toxicity of unripe B. sapida fruit extract (BSE).

Acute toxic effect was investigated in mice of either sex administered BSE 2000 mg/kg. The sub-acute toxicity effects were investigated in mice of either sex that received 28 days repeated administration of BSE (100 and 500 mg/kg, p.o.). Locomotor activity and memory performance were measured as well as seizure vulnerability in PTZ-induced model. Liver enzymes were assessed in the serum. Acetylcholinesterase, oxidative stress parameters and histopathological changes were assessed in the brain and liver tissues.

Signs and symptoms of toxicity such as urination, tremor, depressed locomotion and death were observed in acute toxicity test. Sub-acute dosing caused significant impairment in locomotor activity and memory performance in mice. Seizure threshold was shortened in BSE-treated compared to control mice. Brain acetylcholinesterase activity was significantly increased. Alkaline phosphatase (ALP) was significantly elevated in mice that received BSE (500 mg/kg). Furthermore, BSE caused significant increase in oxidative stress expressed in nitrite, malondialdehyde, reduced glutathione and catalase in the brain and liver tissues. Histological staining revealed neuronal damage of brain hippocampus and hepatocellular swelling and necrosis.

Blighia sapida unripe fruit extract increased susceptibility to seizure and impaired locomotor and memory function. The biochemical and histopathological findings revealed potential toxicity mechanisms related to neurotoxicity and hepatotoxicity.

Blighia sapida K.D. Koenig: A review on its phytochemistry, pharmacological and nutritional properties

ETHNOPHARMACOLOGICAL RELEVANCE

Ackee plant (Blighia sapida K. D. Koenig) (Sapindaceae) is used in Sub-Saharan Africa (where it has its origin) and in different parts of the world (The Caribbean, North and South America, Europe). Traditionally it is used to manage numerous ailments like backache, constipation, cancer, fever in young children, gonorrhea, dysentery, psychosis, hernia, stomach ache, malaria, rheumatism, typhoid etc. It is also used as a cosmetic and food source. The fruit aril is the main constituent of the Jamaican National Dish. This review summarizes its phytochemistry, nutritional properties, ethnobotany and pharmacology. The need to gather up to date information on this plant, to facilitate in vivo and in vitro investigations for verification of some of the local claims necessitated this review.

MATERIALS AND METHODS

A literature search was performed on Ackee using ethno botanical text books and scientific databases such as PubMed, Scopus, EBSCO, Science-direct, Google, Google Scholar and other web sources like records from PROTA, PROSEA, JSTOR and Botanical Dermatology Database.

RESULTS AND DISCUSSION

This review highlights the traditional uses of parts of the Ackee plant: the bark, the leaves, capsules, roots and seeds. They are used in the management of diverse disease conditions such as diarrhoea, conjunctivitis, fever, internal hemorrhage, dysentery, cutaneous skin infections, and bacterial infections amongst others. Only nineteen compounds have been reportedly isolated from the parts of B. sapida; Alkaloids, quinines, polyphenols, and steroids, their glycosides, sesquiterpenes and triterpenes. Some of the plant extracts and its isolated compounds showed anticancer, antimicrobial, antidiarrheal, antioxidant and hypoglycemic activities both in vitro and in vivo. The seed/leaves have also been used as insect repellants and the leaves have been reported to have lethal effects on larvae of various mosquitoes' species. The oil contains a lot of nutrients and may be considered for edible consumption after safety has been confirmed. Hypoglycin A and the less malignant hypoglycin B are found in the unripe aril of Ackee and consumption results in hypoglycemia, vomiting, gluconeogenesis disruption which can result in coma and death. The untapped economic potential of its fruits is glaring in West Africa countries.

CONCLUSION

Though B.sapida has been put to enormous traditional use, the pharmacological studies conducted are not sufficient, most studies are either in-vivo or in-vitro. More work is required (well-designed pharmacological tests, randomized clinical trials) to evaluate these medicinal claims. This review provides a basis for future research. The isolation of more compounds,detailed pharmacological investigations, exploration of food use and detoxification techniques are key areas to investigate.

High Mortality Risk in Hypoglycemic and Dysglycemic Children Admitted at a Referral Hospital in a Non Malaria Tropical Setting of a Low Income Country

INTRODUCTION

Hypoglycemia is a recognized feature of severe malaria but its diagnosis and management remain problematic in resource-limited settings. There is limited data on the burden and prognosis associated with glycemia dysregulation in non-neonate children in non-malaria areas. We prospectively assessed the abnormal blood glucose prevalence and the outcome and risk factors of deaths in critically ill children admitted to a national referral hospital in Laos.

METHODS

Consecutive children (1 month-15 years) admitted to the pediatric ward of Mahosot hospital, were categorized using the integrated management of childhood illness (IMCI). Blood glucose was assessed once on admission through a finger prick using a bedside glucometer. Glycemia levels: hypoglycemia: < 2.2 mmol/L (< 40 mg⁄ dl), low glycemia: 2.2-4.4 mmol/L (40-79 mg⁄ dl), euglycemia: 4.4-8.3 mmol/L (80-149 mg⁄ dl), and hyperglycemia: > 8.3 mmol/L (≥150 mg⁄ dl), were related to the IMCI algorithm and case fatality using univariate and multivariate analysis.

RESULTS

Of 350 children, 62.2% (n = 218) were severely ill and 49.1% (n = 172) had at least one IMCI danger sign. A total of 15 (4.2%, 95%CI: 2.4-6.9) had hypoglycemia, 99 (28.2%, 95%CI: 23.6-33.3) low glycemia, 201 (57.4%, 95% CI: 52.0-62.6) euglycemia and 35 (10.0%, 95% CI: 7.0-13.6) hyperglycemia. Hypoglycemia was associated with longer fasting (p = 0.001) and limited treatment before admission (p = 0.09). Hypoglycemia and hyperglycemia were associated with hypoxemia (SaO2) (p = 0.001). A total of 21 (6.0%) of the children died: 66.6% with hypoglycemic, 6.0% with low glycemic, 5.7% with hyperglycemic and 1.4% with euglycemic groups. A total of 9 (2.5%) deaths occurred during the first 24 hours of admission and 5 (1.7%) within 3 days of hospital discharge. Compared to euglycemic children, hypoglycemic and low glycemic children had a higher rate of early death (20%, p<0.001 and 5%, p = 0.008; respectively). They also had a higher risk of death (OR: 132; 95%CI: 29.0-596.5; p = 0.001; and OR: 4.2; 95%CI: 1.1-15.6; p = 0.02; respectively). In multivariate analyses, hypoglycemia (OR: 197; 95%CI: 33-1173.9), hypoxemia (OR: 5.3; 95%CI: 1.4-20), presence of hepatomegaly (OR: 8.7; 95%CI: 2.0-37.6) and having an illiterate mother (OR: 25.9; 95%CI: 4.2-160.6) were associated with increased risk of death.

CONCLUSION

Hypoglycemia is linked with a high risk of mortality for children in non malaria tropical settings. Blood sugar should be monitored and treatment provided for sick children, especially with danger signs and prolonged fasting. Further evaluations of intervention using thresholds including low glycemia is recommended in resource-limited settings. Research is also needed to determine the significance, prognosis and care of hyperglycemia.

Improving the management of dysglycemia in children in the developing world

Improving the availability of point-of-care (POC) diagnostics for glucose is crucial in resource-constrained settings (RCS). Both hypo and hyperglycemia have an appreciable frequency in the tropics and have been associated with increased risk of deaths in pediatrics units. However, causes of dysglycemia, including hyperglycemia, are numerous and insufficiently documented in RCS. Effective glycemic control with glucose infusion and/or intensive insulin therapy can improve clinical outcomes in western settings. A non-invasive way for insulin administration is not yet available for hyperglycemia. We documented a few causes and developed simple POC treatment of hypoglycemia in RCS. We showed the efficacy of sublingual sugar in two clinical trials. Dextrose gel has been recently tested for neonate mortality. This represents an interesting alternative that should be compared with sublingual sugar in RCS. New studies had to be done to document dysglycemia mechanism, frequency and morbid-mortality, and safe POC treatment in the tropics.

A review of methylene blue treatment for cardiovascular collapse

BACKGROUND

Historically, methylene blue (MB) has been used for multiple purposes, including as an antidote for toxin-induced and hereditary methemoglobinemia, ifosfamide-induced encephalopathy, and ackee fruit and cyanide poisoning; as an aniline dye derivative, antimalarial agent, and antidepressant.

DISCUSSION

Most recently, the use of MB has been advocated as a potential adjunct in the treatment of shock states. Our article reviews the role of MB in septic shock, anaphylactic shock, and toxin-induced shock. MB is proposed to increase blood pressure in these shock states by interfering with guanylate cyclase activity, and preventing cyclic guanosine monophosphate production and vasodilatation.

SUMMARY

MB may be an adjunct in the treatment of septic shock, anaphylactic shock, and toxin-induced shock.

Childhood dysglycemia: prevalence and outcome in a referral hospital

INTRODUCTION

Hypoglycemia is a defining feature of severe malaria and several other infectious diseases in children but the prevalence, significance, and prognosis of abnormal blood glucose, including hyperglycemia, have rarely been addressed in severely ill children in non-malaria endemic areas.

METHODS

In Madagascar, consecutive children (1 month-15 years) admitted to the pediatric ward of a referral hospital, were categorized using the integrated management of childhood illness (IMCI). Samples were taken once on admission for measuring blood glucose concentration. Glycemia levels (hypoglycemia <2.2 mmol/l; low glycemia: 2.2-4.4 mmol/l; normoglycemia >4.4-8.3 mmol/l; and hyperglycemia >8.3 mmol/l) were related to the IMCI algorithm and case fatality. Factors associated with blood glucose concentration and case fatality were analysed using univariate and multivariate analysis.

RESULTS

Of 420 children, 48.1% (n = 202) were severely ill; 3.1% (n = 13) had hypoglycemia; 20.0% (n = 84) low glycemia; 65.9% (n = 277) normoglycemia; and 10.9% (n = 46) hyperglycemia. In univariate analysis, hypoglycemia and hyperglycemia both showed significant increase in the risk of death, as compared to normal blood glucose (RR: 12.2, 95% CI: 6.2-23.7 and RR: 2.5, 95% CI: 1.0-6.2, respectively). Children with low glycemia had no increased risk of death (RR: 1.2, 95% CI: 0.4-3.2) despite a poorer IMCI status on admission. After logistic regression, hypoglycemia (RR: 19.4, 95% CI: 5.0-.74.7, hepatomegaly (RR: 12.2, 95% CI: 3.3-44.9) and coma (RR: 4.8, 95% CI: 1.3-17.6) were the features on admission associated with an increased risk of death.

CONCLUSIONS

Dysglycemia in non-neonates is associated with increased mortality. These findings underline the need for the use of rapid screening tests to initiate early treatment. Alternative treatments such as oral or sublingual administration of glucose should be developed in structures with limited resources.

Fluorometric investigation of the interaction between methylene blue and human serum albumin

The interaction between methylene blue (MB) and human serum albumin (HSA) was investigated by fluorescence spectroscopy and UV-vis absorbance spectroscopy. In the mechanism discussion, it was proved that the fluorescence quenching of HSA by MB is a result of the formation of MB-HSA complex and electrostatic interactions play a major role in stabilizing the complex. The Stern-Volmer quenching constant K(SV) and corresponding thermodynamic parameters DeltaH, DeltaG and DeltaS were calculated. Binding studies concerning the number of binding sites n and apparent binding constant Kb were performed by fluorescence quenching method. The distance r between the donor (HSA) and the acceptor (MB) was obtained according to fluorescence resonance energy transfer (FRET). Wavelength shifts in synchronous fluorescence spectra showed the conformation of HSA molecules is changed in the presence of MB.