Coating rice with mulberry leaves rich in deoxynojirimycin ameliorates hyperglycemia and dyslipidemia in C57BL/KsJ db/db mice

BACKGROUND/OBJECTIVES: Mulberry leaf (ML) has been shown to have an inhibitory effect on α-glucosidase, and suppresses postprandial hyperglycemia, which may be related to its deoxynojirimycin (DNJ) content. This study was conducted to investigate the hypoglycemic and dyslipidemic effects of rice coated with ML rich in DNJ in a type 2 diabetes mouse model. MATERIALS/METHODS: The mice were divided into four groups (n = 8 each): non-diabetic normal control (NC); diabetic control (DM-C), fed with 10% polished rice powder (DM-R); and fed with 10% polished rice powder coated with DNJ-rich ML (DM-DNJR). RESULTS: Supplementation with DNJR for six weeks decreased levels of fasting blood glucose, plasma insulin, triglyceride, total cholesterol, and blood glycosylated hemoglobin; conversely, levels of glucagon-like peptide-1 and high-density lipoprotein-cholesterol showed an increase in the same treatment. In addition, weights of mesenteric, epididymal, and total adipose tissues decreased with DNJR supplementation, when compared with diabetic control db/db mice, while maltase, lactase, and sucrase activity in the small intestine were inhibited. The anti-diabetic effects were marginally greater in the DM-DNJR group than in the DM-R group. CONCLUSIONS: These results suggest that rice coated with ML rich in DNJ can reduce hyperglycemia and hyperlipidemia in db/db mice, and may prove useful for individuals with diabetes.

D-Xylose as a sugar complement regulates blood glucose levels by suppressing phosphoenolpyruvate carboxylase (PEPCK) in streptozotocin-nicotinamide-induced diabetic rats and by enhancing glucose uptake in vitro

BACKGROUND/OBJECTIVES: Type 2 diabetes (T2D) is more frequently diagnosed and is characterized by hyperglycemia and insulin resistance. D-Xylose, a sucrase inhibitor, may be useful as a functional sugar complement to inhibit increases in blood glucose levels. The objective of this study was to investigate the anti-diabetic effects of D-xylose both in vitro and stretpozotocin (STZ)-nicotinamide (NA)-induced models in vivo. MATERIALS/METHODS: Wistar rats were divided into the following groups: (i) normal control; (ii) diabetic control; (iii) diabetic rats supplemented with a diet where 5% of the total sucrose content in the diet was replaced with D-xylose; and (iv) diabetic rats supplemented with a diet where 10% of the total sucrose content in the diet was replaced with D-xylose. These groups were maintained for two weeks. The effects of D-xylose on blood glucose levels were examined using oral glucose tolerance test, insulin secretion assays, histology of liver and pancreas tissues, and analysis of phosphoenolpyruvate carboxylase (PEPCK) expression in liver tissues of a STZ-NA-induced experimental rat model. Levels of glucose uptake and insulin secretion by differentiated C2C12 muscle cells and INS-1 pancreatic beta-cells were analyzed. RESULTS: In vivo, D-xylose supplementation significantly reduced fasting serum glucose levels (P < 0.05), it slightly reduced the area under the glucose curve, and increased insulin levels compared to the diabetic controls. D-Xylose supplementation enhanced the regeneration of pancreas tissue and improved the arrangement of hepatocytes compared to the diabetic controls. Lower levels of PEPCK were detected in the liver tissues of D-xylose-supplemented rats (P < 0.05). In vitro, both 2-NBDG uptake by C2C12 cells and insulin secretion by INS-1 cells were increased with D-xylose supplementation in a dose-dependent manner compared to treatment with glucose alone. CONCLUSIONS: In this study, D-xylose exerted anti-diabetic effects in vivo by regulating blood glucose levels via regeneration of damaged pancreas and liver tissues and regulation of PEPCK, a key rate-limiting enzyme in the process of gluconeogenesis. In vitro, D-xylose induced the uptake of glucose by muscle cells and the secretion of insulin cells by beta-cells. These mechanistic insights will facilitate the development of highly effective strategy for T2D.

Coconut-derived D-xylose affects postprandial glucose and insulin responses in healthy individuals

Metabolic alterations including postprandial hyperglycemia have been implicated in the development of obesity-related diseases. Xylose is a sucrase inhibitor suggested to suppress the postprandial glucose surge. The objectives of this study were to assess the inhibitory effects of two different concentrations of xylose on postprandial glucose and insulin responses and to evaluate its efficacy in the presence of other macronutrients. Randomized double-blind cross-over studies were conducted to examine the effect of D-xylose on postprandial glucose and insulin response following the oral glucose tolerance test (OGTT). In study 1, the overnight-fasted study subjects (n = 49) consumed a test sucrose solution (50 g sucrose in 130 ml water) containing 0, 5, or 7.5 g D-xylose powder. In study 2, the overnight-fasted study subjects (n = 50) consumed a test meal (50 g sucrose in a 60 g muffin and 200 ml sucrose-containing solution). The control meal provided 64.5 g of carbohydrates, 4.5 g of fat, and 10 g of protein. The xylose meal was identical to the control meal except 5 g of xylose was added to the muffin mix. In study 1, the 5 g xylose-containing solutions exhibited significantly lower area under the glucose curve (AUCg) and area under the insulin curve (AUCi) values for 0-15 min (P < 0.0001, P < 0.0001), 0-30 min (P < 0.0001, P < 0.0001), 0-45 min (P < 0.0001, P < 0.0001), 0-60 min (P < 0.0001, P < 0.0001), 0-90 min (P < 0.0001, P < 0.0001) and 0-120 min (P = 0.0071, P = 0.0016). In study 2, the test meal exhibited significantly lower AUCg and AUCi values for 0-15 min (P < 0.0001, P < 0.0001), 0-30 min (P < 0.0001, P < 0.0001), 0-45 min (P < 0.0001, P = 0.0005), 0-60 min (P = 0.0002, P = 0.0025), and 0-90 min (P = 0.0396, P = 0.0246). In conclusion, xylose showed an acute suppressive effect on the postprandial glucose and insulin surges.

Are levels of digestive enzyme activity related to the natural diet in passerine birds?

Digestive capabilities, such as the rates nutrient hydrolysis and absorption, may affect energy intake and ultimately feeding behavior. In birds, a high diversity in gut biochemical capabilities seems to support the existence of a correlation between the morphology and physiology of the intestinal tract and chemical features of the natural diet. However, studies correlating the activity of digestive enzymes and the feeding habits at an evolutionary scale are scarce. We investigated the effect of dietary habits on the digestive physiological characteristics of eight species of passerine birds from Central Chile. The Order Passeriformes is a speciose group with a broad dietary spectrum that includes omnivorous, granivorous and insectivorous species. We measured the activity of three enzymes: maltase, sucrase and aminopeptidase-N. Using an autocorrelation analysis to remove the phylogenetic effect, we found that dietary habits had no effect on enzymatic activity. However, we found that granivorous and omnivorous species had higher levels of disaccharidase activities and insectivores had the lowest. The major difference in enzymatic activity found at the inter-specific level, compared to the reported lower magnitude of enzyme modulation owing to dietary acclimation, suggests that these differences to some extent have a genetic basis. However, the lack of a clear association between diet categories and gut physiology suggested us that dietary categorizations do not always reflect the chemical composition of the ingested food.

Effects of lemon peel extracts on lactate dehydrogenase and sucrase activity of Streptococcus mutans / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of lemon peel extracts (LPE) on the activity of lactate dehydrogenase and sucrase of Streptococcus mutans (Sm).</p><p><b>METHODS</b>After serial dilution with trypticase soy broth (TSB) medium containing 2% glucose, LPE was used as the experimental group, and TSB without LPE as the control group. Sm was added to each group, which was then cultured for 6, 18, 24 and 48 hours in the anaerobic tank. The activity of lactate dehydrogenase(LDH) was measured with the method of oxidation of reduction coenzymeIand the pH value of the culture solution was also detected. The activity of the sucrose was determined with the method of coloration of 3,5-dinitrosalicylic acid.</p><p><b>RESULTS</b>The activity of LDH, sucrase and the changes of solution pH were decreased with the increase of the concentration of LPE (P < 0.01). The activity of LDH were declined from (0.8025 ± 0.0913) × 10(3) U/L to (0.2099 ± 0.0283) × 10(3) U/L; the activity of sucrase were declined from (-0.0107 ± 0.0003) × 10(3) U/L to (-0.0078 ± 0.0002) × 10(3) U/L; the ΔpH were declined from (2.8067 ± 0.0404) to (2.5033 ± 0.0416) (24 h results). The differences were significant between experimental groups and the control group (P < 0.01), and there were also significant differences among experimental groups with different LPE concentration (P < 0.01). The inhibitory effect of acid generation and lactate dehydrogenas' activity of Sm were positively correlated (P < 0.01).</p><p><b>CONCLUSIONS</b>LPE can inhibit the activity of lactate dehydrogenase, sucrase and the acid production capacity of the Sm in a dose dependent manner. The inhibitory effects in logarithmic phase is stronger than that in other phases of growth cycle.</p>

Effect of Na+ ions on pH-dependent conformational changes in brush border sucrase-isomaltase in mice intestine.

Intestinal brush border sucrase-isomaltase (sucrose D-glucosidase E.C. 3.2.1.48, E.C. 3.2.1.10) exhibits pH-dependent stimulatory or inhibitory effects in response to Na+ ions. However, whether the enzyme undergoes conformational modulations as a function of pH and in the presence of alkali metal ions is not known. In this paper, we investigated the structural and functional relationship of purified murine sucrase in response to pH and Na+ ions using UV-CD fluorescence and spectroscopic studies. Kinetic studies revealed that at pH 5.0, the enzyme activation by Na+ ions was V-type, which changed to K-type at pH 7.2, whereas at alkaline pH (8.5), Na+ ions inhibited the enzyme activity and inhibition was uncompetitive in nature, affecting both the Km and Vmax components. Far UV-CD spectra of protein at pH 7.2 in the absence and presence of Na+ were almost overlapping, suggesting that secondary structure of protein was not affected upon addition of the salt. However, near UV-CD spectra indicated marked alterations in the tertiary structure of protein in presence of 50 mM Na+ ions. Increase in pH from 7.2 to 8.5 resulted in a marked rise in fluorescence intensity and red shift in lambda max due to tryptophan residues in the enzyme molecule. These findings suggested that alterations in enzyme activity as a function of pH and Na+ ions was associated with ionization of key amino acid residues together with structural modifications in the enzyme conformation around neutral or alkaline pH.

Effects of Eisenia Bicyclis Extracts and Pill on Blood Glucose and Lipid Profile in Streptozotocin-Induced Diabetic Mice

The objectives of this study were to investigate the antihyperglycemic and hypolipidmic effects of sea oak (Eisenia bicyclis, EB) in the diabetic state and to examine the appropriateness of formulated EB pill for the effects. The various test materials obtained from EB were included in the experimental diets with 15% fat/0.5% cholesterol and fed to streptozotocin-induced diabetic mice weighing 35.0 +/- 0.7 g for three weeks but not in the control diet having the same composition. The test materials were EB dry powder, water and ethanol extracts, viscozyme-treated EB water extract (EB enzyme-TR) and formulated pill containing dry powders of the EB, two kinds of seaweed, black soybean, sesame, onion and garlic. BG was measured during feeding period and serum insulin, lipids and thiobarbituric acid reactive substances (TBARS) and intestinal disaccharidase activities were measured at the end of the three weeks of the feeding. BG increase was lower in the EB enzyme-TR group after 10 days of the experimental diet but lower in EB pill group after 15 days compared with the control group. Serum insulin levels were higher in the EB enzyme-TR and EB pill groups. Intestinal maltase but not sucrase activity was higher in EB enzyme-TR fed group than the control group. Serum levels of total cholesterol and triglyceride were reduced by the EB enzyme-TR and EB pill compared with the control diet. HDL-/total cholesterol was increased by all EB test materials. Serum TBARS levels were lower in the EB ethanol extract and EB pill groups than in the control group and tended to be lower in the other EB groups. It is concluded that the EB enzyme-TR is the best among the EB preparations to be utilized as a functional component for improving blood glucose and lipid profile in diabetic subjects in the future. However, the pill containing low level of the EB powder is also regarded as effective and readily usable when formulated with the several other ingredients of the proper composition. (Supported by the RIC Program of MOCIE, Korea).

Effects of Mulberry Juice and Cake powders on Blood Glucose and Lipid Lowering and Erythrocytic Antioxidative Enzyme Activities in Streptozotocin -Induced Diabetic Rats

The aim of this study was to investigate the effects of mulberry juice and cake powder on blood glucose and lipid status along with intestinal disaccharidase and erythrocyte antioxidative enzyme system in streptozotocin (STZ )-induced diabetic rats. Sprague-Dawley male rats weighing 100 +/- 10 g were randomly assigned to one normal group, and eight STZ-induced diabetic groups: control diet group without mulberry juice and cake powders (DM-C ), three mulberry juice powder groups (0.5%:DM-0.5J, 1%:DM-1J, 2%:DM-2J )and four mulberry cake powder groups (0.25%:DM-0.25C, 0.5%:DM-0.5C, 1%:DM-1C, 2%:DM-2C ). After three-week feeding of each experimental diet, diabetes was induced by intravenous injection of 50 mg/kg body weight of STZ in sodium citrate buffer (pH 4.3 )via tail vein of eight DM groups. Rats were sacrificed at the 9th day of diabetic states. Level of blood glucose was 505 mg/dl in DM-C group but it was 28% and 39% lower in mulberry juice and cake powder fed groups, respectively, than the DM-C group. Activities of maltase, sucrase and lactase in proximal part of small intestine were significantly lower in the mulberry juice and cake powder groups by 42~47% than those of DM-C group. Erythrocytic superoxide dismutase, glutathione peroxidase and catalase activities were significantly reduced by STZ but increased close to normal levels along with less accumulation of thiobarbituric acid reactive substances (TBARS ). Serum levels of triglyceride and total cholesterol and HDL-cholesterol by STZ-DM were reduced and increased respectively, to the normal levels by the mulberry juice and cake powder. Except the levels of TBARS, the effects on the other measure-ments by the various dietary levels of mulberry juice and cake powder were almost same and the effect of the cake powder was most significant at the lowest level. These results indicate that mulberry juice and cake powders have considerable hypoglycemic effect and strengthening antioxidant defense systems at the low levels in diabetic state and may be able to reduce diabetic complications.

Intestinal enzymes during malnutrition & infection in rabbits.

BACKGROUND & OBJECTIVES: Malnutrition plays an important role in the intestinal absorption of nutrients. However, reports are not consistent whether intestinal enzymes are decreased in the presence of malnutrition. It is also not clear whether simultaneous presence of malnutrition and infection adds to the problem of malabsorption of nutrients. The aim of the present study was to determine intestinal functions in terms of concentrations of disaccharidase enzymes during diarrhoea and protein energy malnutrition. METHODS: Concentrations of three disaccharidase enzymes, namely maltase, sucrase and lactase were measured in nine energy-restricted and five control rabbits during diarrhoea induced by rabbit diarrhoeagenic Escherichia coli (RDEC-1). Malnutrition was achieved in the rabbit model by feeding the animals for 30 days with half the amount of food fed to well-nourished control rabbits. Both the energy-restricted and the control groups were challenged by RDEC-1. Diarrhoea occurred on day 1-7 after administration of the strain. After onset of diarrhoea, both groups of rabbits were sacrificed and their intestinal mucosa was examined to determine the concentration of lactase, maltase and sucrase. RESULTS: The energy-restricted animals and controls did not differ significantly for concentrations (units/mg proteins) of lactase (0.65 +/- 0.28 vs 0.56 +/- 0.17 ), maltase (6.20 +/- 2.70 vs 6.47 +/- 1.90) and sucrase (5.42 +/- 2.30 vs 5.13 +/- 1.40) measured during acute infectious diarrhoea. INTERPRETATION & CONCLUSION: The results suggested that the enzymatic functions of the intestinal brush border were not statistically different during diarrhoea among malnourished rabbits compared with their well-nourished counterparts.

Effects of malnutrition on the digestive enzymes of the large bowel of young rhesus monkeys.

The aim of the present study was to investigate the effect of mild-to-moderate protein-energy malnutrition (PEM) and rehabilitation on the digestive enzymes of the large bowel in young rhesus monkeys. The presence of these enzymes has already been reported in the large bowel by many authors. The activities of the digestive enzymes, i.e. lactase, sucrase, maltase, trehalase, glucoamylase, leucine aminopeptidase, alkaline phosphatase and gamma-glutamyl transpeptidase, from different parts of the large bowel were determined in 6 controls, 6 PEM and 6 rehabilitated young rhesus monkeys. These monkeys had been used to study the effect of malnutrition on the small intestine and the results have already been published. There was a significant decrease in the sucrase in the ascending colon (p < 0.05); maltase in all the parts of the large bowel (p < 0.05); and glucoamylase activities (p < 0.05) in the caecum segment of the large bowel in the PEM group. The activity of other enzymes, i.e. lactase, trehalase, alkaline phosphatase, gamma-glutamyl transpeptidase and leucine aminopeptidase, was unaffected in the PEM group. The changes in the enzyme activities recovered on rehabilitation of 21 weeks. The result of this study suggest that even mild-to-moderate malnutrition affects the enzyme activity of the large bowel, which recovers on rehabilitation.

Inhibitory action of berberine on glucose absorption / 药学学报

<p><b>AIM</b>To study the absorption characteristics of berberine and its influence on glucose absorption.</p><p><b>METHODS</b>Rat recirculating perfusion model was used to study berberine absorption characteristics and Caco-2 cell model was used to explore the influence of berberine on disaccharidase, using HPLC to assay the appearance of glucose to indicate enzyme activities.</p><p><b>RESULTS</b>Berberine was found to be hardly absorbed in the intestine (less than 5% in 2.5 h). However, sucrase and maltase activities were found to be inhibited by berberine, its ID50 to sucrase is 1.830 mg.L-1, and showed no dose dependent influence on maltase activity. Berberine also showed influence on glucose absorption. However, this effect is not significant.</p><p><b>CONCLUSION</b>Berberine may act as an alpha-glucosidase inhibitor, which is its main mechanism in diabetes treatment.</p>

Métodos simples de detección de deficiencias de disacaridases / A simple method to detect disaccharides deficiency

A simple method, easy to perform during an endoscopic procedure, fast and inexpensive, that allows detecting deficiencies in lactase, sucrase or maltase activities is presented. Briefly, method consists in placing a duodenal biopsy sample in an adequate vial containing lactose, sucrose or maltose solution during a few minutes, and then, adding a few drops of a glucose reactive from commercial origin. Presence of any enzymatic activity is demonstrated when released glucose from any of the disaccharides chosen reacts with the second reactive, turning solution to a red colour. Its utility is discussed and compared with other diagnostic methods.

Age related effects of organochlorine insecticide lindane on intestinal brush border membrane in rats.

The effect of oral administration of lindane (gamma-HCH) has been studied on the intestine in 10-day, 20-day and 100-day old rats. In 10 day-old suckling pups exposed to lindane, there was a significant decrease in the activities of sucrase (29%), lactase (20%) and that of alkaline phosphatase (24%) compared to control. Sialic acid content of the brush borders was significantly decreased (29%) in 10-day old as well as in 20- and 100-day old rats (20 and 25% respectively), while fucose content of the membranes was significantly enhanced in all the age groups upon pesticide treatment. Among the brush border lipids, cholesterol content was significantly increased in all the age groups studied, the maximum increase of 35% being observed in 10-day-old rats. Membrane phospholipids were also increased in 20- and 100-day old animals (22% each) on lindane exposure. The present studies indicated that brush border membranes of suckling rat intestine were more susceptible to pesticide induced changes compared to older animals.

Some biochemical changes in heme synthesis in iron deficiency.

Some enzymes and intermediates of heme synthesis were determined in blood and urine of 26 women with severe iron deficiency anemia (IDA). Erythrocyte free protoporphyrin was almost doubled and delta-aminolevulinate dehydrase significantly raised. But urinary excretion of delta-aminolevulinic acid and reticulocyte ferrochelatase were significantly reduced in iron deficiency anemia. Hence these could serve as useful indices of iron deficiency and consequent anemia.

Effect of alcohol dependence on the levels of duodenal disaccharidases in human subjects.

BACKGROUND: The aim of the study was to detect the duodenal enzyme activity in patients of alcohol dependence and to compare with non-alcoholic patients of non-ulcer dyspepsia. METHODS: Disaccharidases (lactase, sucrase, maltase) were estimated in 20 non alcoholic patients of non-ulcer dyspepsia and 20 alcoholics admitted to the drug de-addiction and treatment centre of PGIMER, Chandigarh, India. RESULTS: No significant influence of alcohol on enzyme levels in patients of alcohol dependence when compared to patients of non-ulcer dyspepsia was observed. However, a significant decrease in lactase level was noted in patients consuming more than 125 gm/day of alcohol. CONCLUSION: Amount of consumption of alcohol showed decrease in lactase enzyme, but not in maltase and sucrase. There was no effect of duration of alcohol consumption on dissacharidases in the two groups.

Lactase mRNA Expression in Small Intestines of Korean Fetuses and Adults / 대한내과학회지

OBJECTIVE: The specific activity of lactase-phlorizin hydrolase (LPH) is very high at birth and sharply declines after weaning, producing lactose intolerance. The prevalence of lactose intolerance is up to 85% in Korean adults. Molecular basis of the regulatory mechanisms responsible for the decline of LPH specific activity is still unknown. In order to elucidate the molecular mechanisms regulating the LPH expression during development, LPH specific activity and mI4NA level of Korean fetal and adult intestines were compared. METHODS: 20 fetal small intestines (16-27 weeks) were obtained during therapeutic abortion and were divided into 3 equal length. 20 adult jejunal tissues were obtained from patients without small intestinal disease during laparotomy. Mucosal homogenates were prepared for dissacharidases specific activities measurement and total RNA was extracted for northern and slot hvbridization. LPH mRNA level was measured by laser densitometer. RESULTS: LPH specific activities of proximal, middle and distal portion of fetal intestines (n=20) were 36.2 +/- 22.5, 38.6 +/- 23.2 and 23.2 +/- 19.9 mu/mg protein, respectively. LPH specific activity of adult jejunum (n=8) was 5.9 +/- 1.8 mu/mg protein and significantly (p<0.05) lower than those of fetal intestines. However, there was no significant difference in sucrase and trehalase specific activities between fetal intestines and adult jejunum. Although LPH specific activity of adult jejunum was lower than those of fetal intestines, LPH mBNA level of adult jejunum was as high as those of fetal intestines. CONCLUSION: These results show that LPH specific activity and mRNA level do not parallel, indicating the posttranscriptional control of fetal development of LPH expression.

Effect of ischemia/reperfusion on intestinal brush border membrane lipid composition, fluidity and enzyme activities.

Oxygen-derived free radicals are known to be generated during ischemia/reperfusion injury and biomembranes are the prime target of these active species. In order to study the effect of in vivo generated free radicals on intestinal mucosal membrane, brush border membranes (BBM) were isolated from rat small intestine after subjecting to ischemia (I) and ischemia/reperfusion (I/R) injury and their lipid composition and marker enzyme activity were compared with BBM prepared from control animals. No significant alteration in the lipid composition of BBM was observed after I or I/R as compared to control. Membrane fluidity measurements showed that I/R increased the fluidity of BBM. Activity of alkaline phosphatase, one of the marker enzymes for BBM was reduced by I or I/R whereas activity of another BBM enzyme, sucrase was not altered. The decrease in alkaline phosphatase activity was more after reperfusion. In vitro fluidization of BBM using benzyl alcohol indicated that the inactivation of alkaline phosphatase was not due to change in fluidity. These results suggest that free radicals generated during I/R inactivate BBM alkaline phosphatase partially without altering the membrane lipid composition.

Pattern of disaccharidases in chronic diarrhoea and malabsorption

Disaccharide-splitting enzymes were analyzed in the jejunal mucosae of 48 patients suffering from chronic diarrhoea and/or malabsorption, and the results were compared to those of 11 controls. Four [36.4%] of the controls were found to have partial lactase deficiency with a mean ratio of sucrase to lactase activity of 54.8 [SEM +/- 60.06] Significant reduction in the disaccharidases [lactase, sucrase, maltase, and isomaltase] were observed in patients with celiac disease and primary intestinal lymphoma; other groups exhibited variable affection in all disaccharidasas. High incidence of hypolactasia in these patients is the net results of both genetic influence on lactase activity and as a consequence to mucosal injury. It is suggested that further studies should be carried out using intestinal biopsy and direct enzyme assay in a large number of healthy adults

Expression of brush border enzymes in ethanol fed rat intestine.

The effect of feeding ethanol daily for 40 days was studied on various brush border enzymes in rat intestine. Brush border alkaline phosphatase (AP), lactase, gamma-glutamyltranspeptidase (gamma-GTP), p-nitrophenyl (PNP)-beta-D-galactosidase (P < 0.01) and sucrase (P < 0.001) were significantly enhanced while leucine aminopeptidase and PNP-beta-D-glucosidase activities were unaltered in ethanol fed rats compared to the controls. Kinetic studies revealed that an increase in Vmax together with a decrease in affinity in case of gamma-GTP and an increase in Vmax for AP and sucrase were responsible for the observed stimulation of enzyme activities in ethanol administered rats. Significant changes in enzyme activities were observed in different populations of enterocytes along the crypt-villus unit in the ethanol fed animals. These observations suggest that ethanol feeding modifies the brush border enzymes in rat intestine but the underlying mechanisms seem to be distinct in differentiating enterocytes.

Jejunal disaccharidases in protein energy malnutrition and recovery.

The jejunal disaccharidases, sucrase, maltase and lactase, were determined in jejunal biopsies obtained from 43 malnourished children and 10 controls. In the study group, 63% were girls and 93% had severe malnutrition. Lactase activity was significantly reduced in third and fourth degree malnutrition (p < 0.05 and p < 0.005, respectively), but maltase activity was significantly reduced only in the fourth degree malnutrition (p < 0.01). After recovery, maltase and sucrase activities showed a marginally significant increase (p = 0.06), where lactase showed no significant increase (p > 0.05). We conclude that jejunal disaccharidase activity decreases significantly with increasing severity of malnutrition, lactase being the most severely affected and the last to recover.