Antidiabetic, antihyperlipidemic and protective effects of Gladiolus psittacinus on hyperglycemia-mediated oxidative stress in streptozotocin-induced diabetic rats

OBJECTIVES

Gladiolus psittacinus (GP) is an important medicinal plant in folk medicine where its corm is used for treatment of diabetes mellitus. Despite this, there is paucity of scientific information to justify its use as antidiabetic drug. Hence, this study was designed to explore antidiabetic, antihyperlipidemic and effects of aqueous extract of Gladiolus psittacinus (AGP) on hyperglycemia-associated oxidative stress in pancreas, kidney and liver of diabetic rats.

METHODS

Diabetes mellitus (DM) was induced in rats using streptozotocin 50 mg/kg (i.p.). Normal and diabetic rats were treated orally with AGP once a day for 14 days. Antidiabetic effects were evaluated on body weight, fasting blood glucose concentration (FBGC), lipid profiles and serum chemistry. Also, protective effects of AGP were also determined on markers of oxidative stress, antioxidant enzymes and histopathology of pancreas, kidney and liver of diabetic rats.

RESULTS

Treatment with AGP emanated to significant decrease of FBGC (552.67-157.33 mg/dL), increase in body weight (100.01-133.76 g) and positive modulation of lipid parameters in diabetic rats. The alteration in the contents of markers of liver and kidney function were significantly modulated in the diabetic rats upon treatment. Also, oxidative damage and antioxidant depletions in pancreas, kidney and liver were significantly mitigated in treated diabetic rats. Structural aberrations in the histopathology slides of pancreas, kidney and liver were improved upon treatment.

CONCLUSIONS

It can be concluded that AGP could be used in the treatment of diabetes mellitus and its related ailments, thereby justifying its usage in traditional medicine.

Proximate composition, minerals, vitamins, phytochemical constituents and anti-nutrient profile of Beilschmiedia mannii seeds and Combretum racemosum leaves for soup preparation

Several vegetables are used in food preparation to improve the aroma, taste, appearance with less attention on the nutrient and anti-nutrient content. This study investigated the proximate, vitamins, minerals and anti-nutrients profile of Beilschmiedia manni seed and Combretum racemosum leaf. Proximate composition, vitamins, mineral analysis and anti-nutrient profile were determined using standard procedures. The proximate analysis revealed that C. racemosum contained high crude protein (19.18%), crude fat (22.20%) and energy value (449.11 kJ) but low carbohydrate (43.15%) compared to B. mannii with the high carbohydrate (64.25%) content. Phytochemical screening revealed the presence of active phytochemicals in both samples. Thiamine, riboflavin and niacin were significantly (p < 0.05) high in B. mannii compared to C. racemosum. The level of macro minerals in B. mannii seeds and C. racemosum leaves was in the order of K > Ph > Na > Mg > Ca. Beilschmiedia mannii seeds and C. racemosum leaves respectively contained 45.00 mg/100 g and 163.00 mg/100 g oxalate, 70.00 mg/100 g and 113.00 mg/100 g phytate, 58.00 mg/100 g and 209.00 mg/100 g of tannin. This study has revealed that B. mannii seeds and C. racemosum leaves are potential sources of essential nutrients, phytochemicals and could play important role in food enrichment, formulation of dietary supplements and in disease managements.

Safety assessment of oral administration of ethanol extract of Justicia carnea leaf in healthy wistar rats: hematology, antioxidative and histology studies

Background

Consumption of medicinal plants has diverse therapeutic benefits and could also have toxic effect. Justicia carnea is a medicinal plant that is used conventionally as blood tonic from time immemorial in Nigeria. The aim of this study is to evaluate the safety of ethanol extract of J. carnea leaf assessing the hematology indices, organ antioxidant system and histology in healthy male wistar rats.

Methods

Powdered sample was extracted using absolute ethanol and concentrated to obtain a slurry paste of J. carnea ethanol extracts. Acute toxicity was determined in two phases using Lorke method. In subacute study, rats were randomized into six groups of five rats per group: Group 1 (control) received distilled water, group 2, 3, 4, 5, 6 received 50, 100, 500, 800 and 1200 mg/kg body weight of J. carnea ethanol extract once daily using oral gavage. At the end of 14th day of administration, rats were allowed to fast overnight, sacrificed to collect samples for biochemical analysis and histopathological examination.

Results

The LD50 of extract was greater than 5000 mg/kg body weight. Higher doses (> 500 mg/kg) of extract significantly (p < 0.05) increased RBC, hemoglobin and platelet compared to the control. Liver superoxide dismutase (SOD) activity was significantly (p < 0.05) increased at 1200 mg/kg while other tested doses caused no detrimental effect on glutathione, catalase, SOD and malondialdehyde level in liver and kidney. Histopathological examination of liver and kidney showed mild to severe pathological lesion in a dose dependent manner.

Conclusions

The results of this study suggests that ethanol extract of J. carnea leaf is relatively safe, could be beneficial in alleviating hematology related abnormalities without causing adverse effects on endogenous antioxidant system. However, caution should be taken as higher dose at 1200 mg/kg could cause noticeable tissue injury.

Effect of Curculigo pilosa supplemented diet on blood sugar, lipid metabolism, hepatic oxidative stress and carbohydrate metabolism enzymes in streptozotocin-induced diabetic rats

BACKGROUND

Diabetes mellitus (DM) has continued to raise concern globally and Curculigo pilosa (CP) is used for its treatment and management in folkloric medicine. In this study, the in vitro antioxidant abilities of CP and the effects of CP-supplemented diets on blood sugar, lipid metabolism, oxidative stress and key carbohydrate metabolizing enzymes in streptozotocin (STZ)-induced diabetic rats were investigated.

METHODS

Polyphenol contents (total phenolic and total flavonoid) and antioxidant ability of different extracts of CP were determined in vitro. Diabetes mellitus were stimulated in healthy rats by single intraperitoneal administration of 50 mg/kg streptozotocin and it was confirmed by elevated blood glucose level after 3 days. Thirty six rats were distributed into six groups of six rats each and diabetic rats were fed with 5 and 10% CP-supplemented diet for 21 days. Thereafter, the effects of the dietary regimen were evaluated on blood glucose, body weight, hepatic carbohydrate metabolizing enzymes, lipid profile, oxidative stress markers, serum markers of hepatic and renal damages and histopathology studies.

RESULTS

Different extracts of CP contained polyphenol contents and exhibited antioxidant properties in different models used. Diabetic rats showed elevated level of blood glucose and body weight loss. Treatment of diabetic rats with CP-supplemented diet significantly (p < 0.05) lowered the blood glucose and improved body weight loss. Also, the treatment with the CP-supplemented diet significantly (p < 0.05) enhanced the activities of hepatic glycolytic (hexokinase and glucose-6-dehydrogenase) and lowered the gluconeogenic (fructose 1, 6 biphosphatase and glucose-6-phosphatase) enzymes in diabetic rats. The lipid profile, oxidative stress markers and serum markers of hepatic and renal damages were significantly (p < 0.05) restored to near normalcy in the diabetic rats. Histopathological slides also showed improvements in pancreas and hepatic tissues of diabetic rats treated with CP-supplemented diet.

CONCLUSION

Data obtained in this study suggested that CP-supplemented diet could be used as dietary regimen in the management of DM.