J. Welihinda

Effect of Momordica charantia on the glucose tolerance in maturity onset diabetes

Investigations were carried out to evaluate the effect of Momordica charantia on the glucose tolerance of maturity onset diabetic patients. The fruit juice of M. charantia was found to significantly improve the glucose tolerance of 73% of the patients investigated while the other 27% failed to respond.

Oral hypoglycaemic activity of some medicinal plants of Sri Lanka

Investigations were carried out to evaluate the oral hypoglycaemic activity of some Sri Lankan medicinal plants. Approximately 40 plants available locally are reputed to have oral hypoglycaemic activity. Of these, the mostly widely used are (a) Salacia reticulata (Celastraceae) (b) Aegle marmelos (Rutaceae) and (c) Momordica charantia (Cucurbitaceae). Aqueous decoctions of these plants were investigated for their ability to lower the fasting blood glucose level and improve the glucose tolerance in laboratory animals. The results indicate that the aqueous decoctions of all three plants possess significant hypoglycaemic effect. The magnitude of this effect showed time related variation with the three plants. The highest oral hypoglycaemic activity and the maximum improvement of the oral glucose tolerance were associated with the extract of Momordica charantia while the least but significant effects were shown by Salacia reticulata.

Extra-pancreatic effects of Momordica charantia in rats.

The extra pancreatic effects of the oral hypoglycaemic plant Momordica charantia have been investigated in rats. It was found that the fruit juice of this plant caused an increased glucose uptake by tissues in vitro without concomitant increase of tissue respiration. Oral treatment with the juice prior to a glucose load was found to increase the glycogen content of liver and muscle while it had no effect on the triglyceride content of adipose tissue. Pretreatment of fasted rats with M. charantia fruit juice had no significant effect on the gluconeogenic capacity of kidney slices. Similar results were obtained with kidney slices pre-incubated with M. charantia fruit juice.

Carbohydrate-rich foods: glycaemic indices and the effect of constituent macronutrients.

The glycaemic index (GI) ranks foods according to their acute glycaemic impact and is used in planning meals for patients invoking glycaemic control through diet. Kurakkan (Eleusine coracana) flour roti, rice flour roti, atta flour roti, boiled breadfruit (Artocarpus altilis/Artocarpus communis) and boiled legumes (mungbean, cowpea and chickpea) were categorized as low-GI foods (relative to white bread; Prima Crust Top™), and the corresponding GI (± standard error of the mean) values were 70±8, 69±7, 67±9, 64±7, 57±6, 49±8 and 29±5, respectively. Kurakkan flour pittu and wheat flour roti were classified as medium-GI foods with GI values of 85±6 and 72±6. Hoppers, rice flour pittu, wheat flour pittu and Olu-milk rice (seeds of Nymphaea lotus) were categorized as high-GI foods, and the corresponding GI (± standard error of the mean) values were 120±8, 103±7, 101±8 and 91±8, respectively. The GI values significantly (P<0.01) and negatively correlated with the insoluble dietary fibre (ρ = − 0.780), soluble dietary fibre (ρ = − 0.712) and protein (ρ = − 0.738) contents in grams per 100 g digestible starch containing foods.

A linkage study of the locus for X-linked Charcot-Marie-Tooth disease

A large family with Charcot‐Marie‐Tooth disease, showing a probable X‐linked incomplete dominant inheritance, was studied by linkage analysis. Results, obtained by the use of X chromosome specific DNA probes of known regional location, suggest that the disease locus is linked to the DXYS1 locus (ž=2.59 at θ= 0.00) and to the DXS14 locus and, places the disease locus between the DXYS1 locus and the DXS14 locus, near the centromere of the X chromosome. Together with the published data, a distance of 13 cM (ž= 6.95) was assessed between the disease locus and the DXYS1 locus.

Do Sri Lankan meals help decrease blood glucose response

OBJECTIVE The prevalence of diabetes mellitus (DM) has rapidly increased in Asian countries including Sri Lanka during the past decade. Scientific data on postprandial glycaemic influence of common meals is essential when formulating diets. Objectives of this study were to analyse glycaemic indices (GI) of five common meals and effects of macronutrients, sources of carbohydrates, and physicochemical properties of starch on observed GI values. DESIGN The meals analysed were; 1 - red rice (AT 353) meal, 2 - red rice mixed meal, 3 - stringhopper (wheat flour) meal, 4 - stringhopper (rice flour) meal, 5 - manioc (Manihot esculenta) meal. SETTING University of Sri Jayewardenepura. SUBJECTS Healthy individuals (n=10; age: 20-30 years). MEASUREMENTS GI of each meal was calculated according to FAO/WHO guidelines by taking the ratio of incremental area under blood glucose curve (IAUC) of test and the standard. RESULTS GI of meals 1-5 were 99 +/- 10, 60 +/- 5, 104 +/- 7, 102 +/- 11 and 120 +/- 9 respectively. The glycaemic response to rice mixed meal was significantly lower (p<0.05) than the others. The total dietary fibre content showed a significant negative correlation (p=0.044) with the GI value while the protein showed a non-significant negative relationship (p>0.05). Red rice had a combination of intact, swollen and disintegrated starch granules while string hoppers and manioc showed only the latter two types. CONCLUSION The rice mixed meal has the lowest glycaemic index. Presence of dietary fibre and a legume reduces the glycaemic response. Cooking may change the glycaemic response of certain food.

Chemical compositions and glycemic responses to banana varieties

Chemical compositions and glycemic indices of four varieties of banana (Musa spp.) (kolikuttu–Silk AAB, embul–Mysore AAB, anamalu-Gros Michel AAA, seeni kesel–Pisang Awak ABB) were determined. Silk, Gros Michel, Pisang Awak and Mysore contained the highest percentages of starch (14%), sucrose (38%), free glucose (29%) and fructose (58%) as a percentage of the total available carbohydrate content respectively. Total dietary fiber contents of four varieties ranged from 2.7 to 5.3%. Glycemic indices of Silk, Mysore, Gros Michel and Pisang Awak were 61 ± 5, 61 ± 6, 67 ± 7, 69 ± 9 and can be categorized as low against white bread as the standard. A single banana of the four varieties elicited a low glycemic load. Thus, consumption of a banana from any of these varieties can be recommended as a snack for healthy or diabetic patients who are under dietary management or pharmacological drugs to regulate blood glucose responses in between meals.

Glycaemic indices of three Sri Lankan wheat bread varieties and a bread-lentil meal

The glycaemic index (GI) concept ranks individual foods and mixed meals according to the blood glucose response. Low-GI foods with a slow and prolonged glycaemic response are beneficial for diabetic people, and several advantages have been suggested also for non-diabetic individuals. The recent investigations imply an increasing prevalence of diabetes mellitus in Sri Lanka. Thus, the present study was designed primarily to determine the glycaemic indices of some bread varieties in Sri Lanka as bread has become a staple diet among most of the urban people. A second objective was to observe the effects of macronutrients and physicochemical properties of starch on GI. Glycaemic responses were estimated according to FAO/WHO guidelines and both glucose and white bread were used as standards. Non-diabetic individuals aged 22–30 years (n=10) participated in the study. The test meals included white sliced bread, wholemeal bread, ordinary white bread and a mixed meal of wholemeal bread with lentil curry. The GI values (±standard error of the mean) of the meals were 77±6, 77±6, 80±4, 61±6, respectively (with glucose as the standard). The GI values of the bread varieties or the meal did not differ significantly (P >0.05). However, the meal can be categorized as a medium-GI food while the other bread varieties belong to the high-GI food group. A significant negative correlation was obtained with protein (P=0.042) and fat (P=0.039) contents of the food items and GI. Although the GI values of the foods are not significantly different, the inclusion of lentils caused the GI to decrease from a high-GI category to a medium-GI category. According to the present study, a ratio of 1.36 can be used to interconvert the GI values obtained with the two standards.