Ngozi Paulinus Okolie

PROTECTIVE EFFECT OF ETHANOLIC LEAF EXTRACT OF ANNONA MURICATA LINN ON SOME EARLY EVENTS IN CYCAS-INDUCED COLORECTAL CARCINOGENESIS IN RATS

The study was carried out to investigate the effect of ethanolic leaf extract of Annona muricata, ELAM on some early changes in cycas-induced colorectal carcinogenesis in rats. 7 groups of male Wistar rats (10 rats /group) were used. Groups were fed either mash alone or mash mixed with 5 % (w/w) cycas leaf powder. ELAM (100 mg/kg body weight) was administered before, simultaneously with, or after exposure to 5 % (w/w) cycas, for 30 days. After sacrifice, colon sections were dissected out for histological and some biochemical analysis. Results showed that cycas alone caused significant decreases in colon total protein (p <0.05), but administration of cycas with ELAM (irrespective of which came first) led to reversal of these decreases, with colon protein restored to levels higher than values for controls. Cycas-induced increases in LDH were significantly (p <0.05) reduced by ELAM. Colon SOD, catalase and GPx activities were significantly decreased in the group fed cycas, while these enzymes were significantly increased above control values in the groups fed both cycas and ELAM (p <0.05). In addition, the cycas-treated group had significant elevation of colon MDA, but MDA levels were significantly lowered in the groups fed cycas and ELAM. Histology results revealed early cancer-related morphological changes in the cycas group, including mucosal erosion, oedema and glandular hyperplasia. These lesions were absent in the groups given ELAM and cycas, irrespective of the duration of ELAM exposure. These results demonstrate evidence for protective role of ELAM in early biochemical events associated with colorectal carcinogenesis in rats.

A C OMPARATIVE STUDY OF MALONDIALDEHYDE CONTENTS OF SOME MEAT AND FISH SAMPLES PROCESSED BY DIFFERENT METHODS

The effect of different processing methods on the malondialdehyde, MDA c ontents of 7 popular samples of fresh meat and fish eaten in Nigeria, was investigated. The MDA levels were assayed in a colorimetric reaction with thiobarbituric acid in fresh samples of beef, pork, turkey, chicken, snail, catfish and goat meat p rocessed by boiling, frying , roasting and freezing . Results obtained showed that all processing methods led to significant increases in MDA contents of the samples studied relative to their fresh, unprocessed counterparts (p goat meat > catfish > turkey > chicken > snail > pork. The MDA content of frozen mackerel was significantly increased by boili ng and frying and by further freezing (p < 0.05). These results suggest that while all th e processing methods may be unsafe, the frying of boiled meat and fish may be particularly deleterious to consumer health, in view of the well known mutagenic and carcinogenic effects of MDA .

A comparative study of effect of oral chronic cyanide administration on some rabbit tissue ATPases.

The effect of oral KCN administration on Na(+)-K(+)-ATPase, Ca(2+)-ATPase and Mg(2+)-ATPase activities was studied in some rabbit tissues. Generally, the order of activity of the enzymes was kidney > liver > ileum > colon. There were significant decreases (P < 0.05) in the activities of all the ATPases in the tissues of KCN-treated rabbits relative to controls. The decreases in Na(+)-K(+)-ATPase and Ca(2+)-ATPase activities were most pronounced in liver and kidney. The decreases in ATPases suggest impairment of membrane function as a result of the toxic effect of cyanide.

EFFECT OF AQUEOUS LEAF EXTRACT OF EUPHORBIA HETEROPHYLLA ON KIDNEY, LIVER AND PANCREATIC FUNCTIONS AND PLASMA ELECTROLYTES IN RABBITS

Although the use of Euphorbia heterophylla as herbal laxative in Nigeria is associated with severe and sometimes life - threatening side effects, not much is known about the toxic effect of the herb. This study was designe d to assess the effect of aqueous leaf extract of the plant on some vital organ functions in rab bits. Three groups of rabbits ( six rabbits/group s ) were used. Two groups received either 10 mg or 20 mg of aqueous extract/kg body weight for 18 days via oro - ga stric route. Members of the third group received saline and served as controls. On the 18 th day, the rabbits were sacrificed following an overnight fast and blood samples were collected via the ear veins in heparinised bottles for plasma preparation. The k idney, liver and pancreas were quickly dissected out and weighed portions were used in preparation of tissue homogenates for biochemical analysis. Using standard procedures, alkaline phosphatase (ALP), aspartate transaminase (AST) gamma glutamyl transferas e (GGT), alanine transaminase (ALT), electrolytes (Na + , K + and Cl ), blood urea nitro gen (BUN), creatinine, total proteins and albumin were assayed either in tissues or in plasma or both. The results obtained showed that the extract significantly and dose - dependently decreased plasma Na + , urea and creatinine , while plasma Cl and K + were significantly elevated relative to control (P < 0.05). T he extract also significantly increased fasting blood glucose and plasma amylase (P < 0.05). On the other hand, pan creatic protein and pancreatic amylase were significantly decreased. The plasma levels of GGT, AST and ALP were significantly higher in the extract - treated rabbits , while the activities of the en zymes were significantly decreased in the liver (P < 0.05). A LT did not follow a definite pattern, initially significantly decreasing in plasma and then increasing at the higher extract dose, while the activity of the enzyme significantly increased dose - dependently in the liver (P < 0.05 ). The extract significantly decreased liver and kidney total protein as well as plasma total protein and plasma albumin (P < 0.05). These results suggest that E. heterophylla may have toxic effects on vi tal organs and may provide a basis for rationalizing the adverse health effects f requently associated with the use of this herbal laxative.

A COMPARATIVE STUDY OF RHODANESE ACTIVITY IN SOME LIZARD SPECIES

Abstract 1. Rhodanese activity has been determined in some organs of three species of lizards, namely: rainbow lizard, wall gecko and skink. 2. While the activity was significantly higher in the livers of all the species compared to that in the kidney, small intestine and the brain, there were significant differences in the enzyme in the livers of the different species. The activity was highest in the liver of the rainbow lizard followed by that of wall gecko and then skink. 3. The order of activity of the enzyme in the organs of the rainbow lizard was liver > kidney > small intestine > brain. 4. The high level of rhodanese in lizard tissues suggests that the enzyme may be involved in roles other than cyanide detoxification.