{"id":27843,"date":"2019-06-25T10:54:00","date_gmt":"2019-06-25T10:54:00","guid":{"rendered":"http:\/\/biomedpharmajournal.org\/?p=27843"},"modified":"2020-04-23T04:43:57","modified_gmt":"2020-04-23T04:43:57","slug":"evaluation-of-alpha-glucosidase-inhibitory-activity-of-vinca-rosea","status":"publish","type":"post","link":"https:\/\/biomedpharmajournal.org\/staging\/vol12no2\/evaluation-of-alpha-glucosidase-inhibitory-activity-of-vinca-rosea\/","title":{"rendered":"Evaluation of Alpha-Glucosidase Inhibitory Activity of Vinca Rosea"},"content":{"rendered":"

Introduction<\/strong><\/p>\n

Diabetes mellitus (DM) is one of the major health issues worldwide and its increasing trend is expected to be doubled by 2030.1<\/sup> International Diabetes Federation (IDF), states that the prevalence of diabetes mellitus is more common among developing countries where people take high-calorie food in their diets and lack of physical exercises.1<\/sup>\u00a0The onset of diabetes mellitus differs from individual to individual, but middle aged and adults are always at higher risk. Type II Diabetes mellitus is more common and exhibits approximately 90%\u201395% of all cases.2<\/sup> Type II diabetes mellitus is caused by the decreased production of insulin by the pancreatic \u03b2-cells or due to excessive assimilation of glucose which leads to insulin resistance\u00a0resulting in hyperglycaemia.3,4<\/sup> Chronic hyperglycaemia can lead to several microvascular and macrovascular complications.<\/p>\n

\ud835\udefc-glucosidase is an enzyme which is responsible for the conversion of complex carbohydrates into glucose. This enzyme acts by delaying the breakdown of complex carbohydrates into glucose and reduces its absorption rate from the gut which results in reduction of postprandial blood sugar level.5<\/sup> This therapeutic approach has been recommended by the Third Asia-Pacific Region Diabetes Treatment Guidelines as the first-line of treatment for lowering postprandial hyperglycaemia.6<\/sup><\/p>\n

Although commercially available \u03b1-glucosidase inhibitors like Voglibose and Acarbose are used effectively in controlling blood glucose levels, they have been associated with serious gastrointestinal side effects. Therefore, there is a need to search for an alternative that can exhibit \u03b1-glucosidase inhibitory activity without side effects.7<\/sup><\/p>\n

Medicinal plants have been used since ages to treatment various ailments. Vinca rosea<\/em> (C. roseus) Linn, commonly known as Madagascar periwinkle is a flowering herb that belongs to Apocynaceae family. They contain dimeric alkaloids, vinacristine and vinblastine that are used as anticancer drugs, while roots have ajmalicine and serpentine which is used to treat hypertension.8<\/sup> The leaves are used traditionally to control diabetes worldwide, including India. Earlier studies on laboratory animals have reported that the leaf extracts possess a very good antihyperglycemic and hypotensive activity. Leaf juice of the plant was noted to reduce blood glucose in alloxan induced diabetic rabbits. Leaves and twigs have been reported to reduce blood glucose level \u00a0in alloxan induced diabetic rats.9<\/sup> Apart from this the plant is also used in treating malaria and sore throat. Literature shows that these plants are used in the regulation of menstrual cycles and as euphoriant.10<\/sup><\/p>\n

The present study was aimed to compare the alpha glucosidase inhibitory activity of methanolic extract of leaves and flowers of Catharanthus roseus<\/em>.<\/p>\n

Materials and Methods<\/strong><\/p>\n

Chemicals<\/strong>
\n\u03b1-glucosidase was purchased from Sigma-Aldrich, Bangalore.<\/p>\n

Plant Materials<\/strong><\/p>\n

The plant parts were identified and authenticated by Department of Botany, National Institute of Siddha-Chennai.<\/p>\n

Extraction of Plant Material<\/strong>11<\/sup><\/p>\n

The Leaves and flowers were removed separately, air dried under shade, powdered and stored in an airtight container. The powdered material was extracted with methanol (80%) by the process of soxhlation. The filtrate was concentrated at reduced pressure by rotary flash vacuum evaporator.<\/p>\n

Determination of yeast alpha-glucosidase inhibitor activity12<\/sup><\/strong><\/p>\n

The yeast alpha glucosidase was dissolved in 100 mM phosphate buffer pH 6.8 and was used as the enzyme source. P-Nitrophenyl-\u03b1-D-glucopyranoside was used as the substrate. Acarbose was used as the Standard drug for alpha glucosidase inhibitor. Plant extracts were used in the concentration ranging from 20-200 \u00b5g\/ml. Different concentrations of leaf and flower extracts of Vinca rosea<\/em> and Acarbose (0.025, 0.05, 0.1, 0.15, 0.2 mg\/ml) was mixed with 320 \u00b5l of 100 mM phosphate buffer. The mixture was incubated \u00a0at 30 \u00b0C for 5 minutes. 3 ml of 50 mM sodium hydroxide was added to the mixture and the absorbance was read at 410 nm using spectrophotometer. The control samples were prepared without adding any plant extracts. The % inhibition was calculated according to the formula.<\/p>\n

\"Formula<\/p>\n

Results and Discussion<\/strong><\/p>\n

Diabetes mellitus is a well-known metabolic disorder, which is characterized by an elevated blood glucose level. The reason for this condition is either due to the loss of production of insulin by the pancreas or reduced response by the cells to the produced insulin or both. Controlling the postprandial hyperglycaemia is of prime importance in management of Type II Diabetes mellitus. \u03b1-Glucosidase plays a vital role in digestion of complex carbohydrate to glucose, hence its inhibition is considered as one of the targets for managing postprandial hyperglycaemia. Acarbose has \u03b1-glucosidase and \u03b1-amylase inhibitory activity but known to cause \u00a0side effects such as bloating, flatulence and diarrhoea.13<\/sup><\/p>\n

The use of herbal drugs in treating Diabetes mellitus and its complications is growing globally. In the present study, inhibitory activity of methanolic extracts of leaves and flowers of Vinca rosea<\/em> on yeast alpha glucosidase was investigated. The results are given in Table 1. Percentage of \u03b1-Glucosidase inhibition by the leaves and flowers extract were plotted as a function of concentration in comparison with Acarbose (Fig.1). All the extracts showed a concentration-dependent inhibition of \u03b1-glucosidase. The standard drug Acarbose showed highest \u03b1-glucosidase inhibition (62.36%) followed by leaf (57.87%) and flower (48.31%) extract\u00a0\u00a0 respectively at their highest concentrations tested.<\/p>\n

Table 1: \u03b1-glucosidase inhibitory effects of methanolic extract of leaves and flowers of Vinca rosea<\/em> and Acarbose.<\/strong><\/p>\n\n\n\n\n\n\n\n\n\n
Concentration\u00a0<\/strong>Mg\/ml<\/strong><\/td>\n%\u00a0 \u03b1- glucosidase inhibition<\/strong><\/td>\n<\/tr>\n
Flower extract<\/strong><\/td>\nLeaf extract<\/strong><\/td>\nAcarbose<\/strong><\/td>\n<\/tr>\n
0.025<\/td>\n7.30\u00b13.2<\/td>\n9.55\u00b13.0<\/td>\n20.22\u00b13.1<\/td>\n<\/tr>\n
0.05<\/td>\n18.54\u00b13.1<\/td>\n24.72\u00b13.0<\/td>\n32.02\u00b13.1<\/td>\n<\/tr>\n
0.1<\/td>\n29.78\u00b13.0<\/td>\n34.27\u00b12.8<\/td>\n40.45\u00b13.0<\/td>\n<\/tr>\n
0.15<\/td>\n35.96\u00b13.3<\/td>\n42.70\u00b13.1<\/td>\n50.00\u00b13.6<\/td>\n<\/tr>\n
0.2<\/td>\n48.31\u00b13.2<\/td>\n57.87\u00b13.3<\/td>\n62.36\u00b13.1<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u00a0<\/strong><\/p>\n\n\n\n
\"Figure<\/td>\nFigure 1: Percentage <\/strong>\u03b1-glucosidase inhibitory effects of methanolic extract of leaves and flowers of Vinca rosea<\/em> and Acarbose.<\/strong><\/p>\n

 <\/p>\n

Click here to view figure<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

Conclusion<\/strong><\/p>\n

The results of the present study showed that methanolic leaves and flowers extract of Vinca rosea<\/em> possess \u03b1-glucosidase inhibitor activity which may be useful in management of Type II Diabetes mellitus. The leaves extract showed a better activity when compared to flowers extract. However these effects need to be confirmed by testing these extracts of Vinca rosea<\/em> in different in– vivo<\/em> models before developing into a new antidiabetic agents.<\/p>\n

Conflict of Interest<\/strong><\/p>\n

There are no conflicts of interest.<\/p>\n

References<\/strong><\/p>\n

    \n
  1. International Diabetes Federation (IDF). Diabetes Atlas. 5th\u00a0ed. Brussels, Belgium: International Diabetes Federation; 2011.<\/li>\n
  2. Wild S, Roglic G, Green A, Sicree R, King H. Global prevalence of diabetes: Estimates for the year 2000 and projections for 2030. Diabetes Care.2004; 27:1047-53.<\/li>\n
  3. Ardisson Korat AV, Willett WC, Hu FB. Diet, lifestyle, and genetic risk factors for type 2 diabetes: A review from the Nurses’ Health Study, Nurses’ Health Study 2, and Health Professionals’ Follow-up Study. Curr Nutr Rep. 2014; 3:345-54.<\/li>\n
  4. Patti ME, Corvera S. The role of mitochondria in the pathogenesis of type 2 diabetes. Endocr Rev. 2010; 31:364-95.<\/li>\n
  5. Subramanian R, Asmawi AZ, Sadikun A, J Pol Biochem Soc<\/em>.2008, 55:391-398.<\/li>\n
  6. P. Li, B. Bai, J. Ye, et al., Reviews on preparation and determination of \u03b1-glucosidase inhibitor, Food Sci. 29:2008; 617\u2013619.<\/li>\n
  7. Playford RJ, Pither C, Gao R, Middleton SJ. Use of the alpha glucosidase inhibitor acarbose in patients with ‘Middleton syndrome’: normal gastric anatomy but with accelerated gastric emptying causing postprandial reactive hypoglycemia and diarrhea.\u00a0Can J Gastroenterol<\/em>. 2013;27(7):403-4.<\/li>\n
  8. Jaleel, C.A., R. Gopi, G.M.A. Lakshmanan and R. Panneerselvam.\u00a0Triadimefon induced changes in the antioxidant metabolism and ajmalicine production in\u00a0Catharanthus roseus<\/em>(L.) G. Don. Plant Sci.2006; 171: 271-276.<\/li>\n
  9. Jayanthi M,\u00a0 Sowbala\u00a0 N,\u00a0 Rajalakshmi\u00a0 G,\u00a0 Kanagavalli\u00a0 U, Sivakumar\u00a0 \u00a0 Study\u00a0 of\u00a0 anti-hyperglycemic\u00a0 effect\u00a0 of\u00a0 Catharanthus\u00a0 roseus<\/em>\u00a0 in\u00a0 alloxan-induced\u00a0 diabetic\u00a0 rats.\u00a0 Int\u00a0 J Pharm Pharm Sci. 2010; 2:114-116.<\/li>\n
  10. Bhutkar MA, Bhise SB. Comparative studies on antioxidant properties of Catharanthus rosea <\/em>and Catharanthus alba<\/em>. Int J Pharm Tech Res., 2011; 3(3):1551-1556.<\/li>\n
  11. Khandelwal KR. Practical Pharmacognosy: Techniques and Experiments, Nirali Prakashan, Pune. 2005, 149-53.<\/li>\n
  12. Jung M, Park M, Chul HL, Kang Y, Seok-Kang E, Ki-Kim S. Antidiabetic agents from medicinal plants.\u00a0Curr Med Chem.\u00a02006;13:1\u201316.<\/li>\n
  13. Vichayanrat A, Ploybutr S, Tunlakit M, Watanakejorn P. Efficacy and safety of voglibose in comparison with acarbose in type 2 diabetic patients.\u00a0Diabetes Res Clin Pract.\u00a02002;55:99\u2013103.<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"

    Introduction Diabetes mellitus (DM) is one of the major health […]<\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[69],"tags":[],"class_list":["post-27843","post","type-post","status-publish","format-standard","hentry","category-vol12no2"],"_links":{"self":[{"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/posts\/27843","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/comments?post=27843"}],"version-history":[{"count":5,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/posts\/27843\/revisions"}],"predecessor-version":[{"id":32107,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/posts\/27843\/revisions\/32107"}],"wp:attachment":[{"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/media?parent=27843"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/categories?post=27843"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/tags?post=27843"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}