OCT is a powerful tool for detection of physiological functions of micro organs underneath the human skin surface, besides the clinical application to ophthalmology, as recently demonstrated by the authors’ group. In particular, dynamics of peripheral vessels can be observed clearly in the time-sequential OCT images. Among the vascular system, only the small artery has two physiological functions both for the elastic artery and for muscle-controlled one. It, therefore, is important for dynamic analysis of blood flow and circulation. In the time-sequential OCT images obtained with 25 frames/sec, it is found that the small artery makes a sharp response to sound stress for contraction and expansion while it continues pulsation in synchronization with the heartbeats. This result indicates that the small artery exhibits clearly the two physiological functions for blood flow and circulation. In response to sound stress, blood flow is controlled effectively by thickness change of the tunica media which consists of five to six layers of smooth muscles. It is thus found that the thickness of the tunica media changes remarkably in response to external stress, which shows the activity of the sympathetic nerve. The dynamic analysis of the small artery presented here will allow us not only to understand the mechanism of blood flow control and also to detect abnormal physiological functions in the whole vascular system.
The word diabetes was coined by the Greek physician Aretaeus in the first century AD Diabetes mellitus has been known since ages and sweetness of urine has been mentioned in Ayurveda by Sushruta. Its pharmacotherapy is 80 year old. The presence of sugar in the urine of diabetics was demonstrated by Dobson in 1755 [
Diabetic patients are diagnosed by blood or urinary glucose measurement through different techniques. On the basis of etiology DM (Diabetes mellitus) are categories mainly two types viz:
1) Primary Diabetes (Type I or Insulin Dependent Diabetes Mellitus).
2) Secondary Diabetes (Type II or Non Iinsulin Dependent Diabetes Mellitus).
Primary DM (Diabetes mellitus) clinically dependent on insulin due to there is decrease in the number of β-cells in the islets of langerhans and thus there is absolute deficiency of insulin hence this is known as Insulin Dependent Diabetes Mellitus (IDDM) or Type I. The main treatment for this Type I of DM (Diabetes mellitus) is insulin.
Secondary DM (Diabetes mellitus) is referred as Type II or Non Insulin Dependent Diabetes Mellitus (NIDDM) because these types of patients are insulin resistances as well as loss of insulin secretion contributes to the onset of disease. The patients are usually obese and the treatment is usually dietary, through supplementary oral Hypoglycemic drugs.
As the complications induced by diabetes mellitus are very serious and goes to worst day by day hence, there is potent need of medicine to cure the diabetes mellitus. In this review we will go through the all the possible cure available to preventing the complications and its limitation also, to finding out the alternatives of these synthetic drugs, having no or few side effects with low price and ease to reach the common people.
Basic therapeutic approach to treat diabetes may be to inhibit the absorption of glucose by retarding the action of gastro-intestinal enzymes such as α-glucosidase and α-amylase. Because the complication of disease is mainly due to the higher glucose level in blood which dysfunction the other organs of body. Thus we can say that the effective α-glucosidase inhibitors may serves as chemotherapeutic agents for clinic use in the treatment of diabetes and obesity [4,5].
Insulin increases glucose uptake in cells by stimulating the translocation of the glucose transporter GLUT4 from intracellular sites to the cell surface [6,7]. Insulin circulates in blood as the free monomer and its half life in plasma is about 5 - 6 min in normal subjects. Although glucose is the principal stimulus to insulin secretion in human beings, this process is tightly regulated by the coordinated of nutrients, gastrointestinal and pancreatic hormones and autonomic neurotransmitters [
Oral Hypoglycemic drugs are those drugs that lower blood glucose level and taken orally. These drugs are synthetic and complex organic substances. Hence the search for oral active drugs is in demand.
First Generation Drugs a) Tolbutamine;
b) Chloropropamide;
c) Acetohexamide;
d) Tolazmde.
Second Generation Drugs a) Gilbenclamide;
b) Glipizide;
c) Gliclazide.
a) Phenformin;
b) Metformin.
a) Acarbose;
b) Guar Gum.
These drugs are effective in diabetes but having some limitations such as hypoglycemia occurs with regular use of sulfonylurea compounds but occurrences are much fewer than with insulin therapy. It is prescribed by doctors that biguanids should not use in patients with renal diseases. On the other hand the main side effect of Acarbose is flatulence [
The current literature also shows that metallopharmaceuticals is an area of growing interest as is evident through the clinical trials that are being conducted worldwide for the usages of metals in therapeutics. Metallotherapy is a new therapeutic strategy to treat diabetes with metal complexes. It is first studied by Coulson and Dandona in 1980 that ZnCl2 stimulate lipogenesis in rat adipocytes similarly to the action of Insulin. In three decades there are many researchers reported insulin-mimetic activity, α-glucosidase and α-amylase inhibition with different coordination of different ligand with transition metals. However the strategies to treat the diabetes mellitus through metal complexes are in early stage hence there are no side effects reported at all. Some metal complexes are in trial stage for treating diabetes.
There are many herbal products/herbal extracts are reported to treat the diabetes mellitus, we can classify these drugs according to their mode of action as:
3.1.4.1. Extracts/Drugs Act as α-Glucisidase or α-Amylase Inhibitor These types of drugs/extracts are able to reduce the blood glucose level by inhibiting the gastric enzymes which is obligatory for the break the polysaccharides in to the simple sugar.
The aqueous and methanolic extract of Syzgium cumini (seed) and Pisidium guajava (leaves) shows α-amylase inhibition [
3.1.4.2. Extracts/Drugs Increases Insulin Secretion or β-Cell Regeneration These types of drugs are directly concern with the Type I or IDDM diabetes which are disable to secreting the less or few amount of insulin.
Radix of Acorus calamus is used as in the therapy of diabetes in traditional folk medicine of America and Indonesia, this sensitize the insulin activity of its ethyl acetate extract [
3.1.4.3. Extracts/Drugs Act as Hypoglycemic, Antihyperglycemic or Antidiabetic Effect These classes of herbal drugs reduce the blood glucose level directly, this may be also used to treat the both type of diabetes mellitus (IDDM and NIDDM).
Mangifera indica Linn. (Locally known as mango tree) has antidiabetic property, ethanolic and water extract of leaves and stem bark of Mangifera indica shows significant antihyperglycemic effect [
3.1.4.4. Extracts/Drugs Dealing with the Complications of Diabetes Mellitus Diabetes mellitus is metabolic syndrome characterized by deregulation in carbohydrate metabolism associated with defect in insulin secretion or action by which glucose level of blood increases, the different type of complication occurred. To treat these type of problem many herbal drugs/extract may play a key role.
The aqueous extract of bark of Ficus religiosa Linn reduces oxidative stress in Type II diabetes mice model [
India has a great ancient heritage of traditional medicine. The material medica of Indian provides much information on ethnic folklore practices and traditional aspects of therapeutically important natural products [26,27]. Indian traditional medicine is based on various systems, including Ayurveda, Siddha and Unani (ASU). With the emerging interest of the world in adopting and studied traditional systems and in exploiting their potential from different healthcare perspectives, it is necessary to listing some of plants which are used to curing the diabetes from ancient time are listed in [28-31]
There are several herbal drugs are formulated according to traditional and modern knowledge of ethanobotany. Bio-active molecules have been cross checked on diabetic models and several are in trail courses. Some of trails are as:
Wendell D. Winters (2003) et al. [
Ikuko Kimura (1999) et al. [
In the management of diabetes Type II a trail of Vijayasar (Pterocarpus marsupium) had done in different location in India by ICMR group to check the efficacy of Vijayasar in contrast of synthetic drug Tolbutamide. Study shows that Vijayasar is an effective blood glucose lowering traditional Indian plant agent, its glycemic effect being comparable to that of Tolbutamide in treatment
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patient with Type II diabetes and free from any significant side effect [
Mordern treatments (synthetic drugs) of diabetes mellitus are focused on lowering the glucose level to normal level into blood while traditional medicines/drugs/extracts are complex in nature as well as their mechanism of action. Ayurvedic formulations, often complex with several herbal-mineral ingredients, are governed by well-described pharmacological principles of preparation, compatibility and administration.
Classic texts contain descriptions of classic formulations, traditional Ayurvedic practitioners often modify them to suit the individual constitution (prakriti), which confers genetic predisposition toward disease and therapy response, and is vital to ensure medication safety [
As we mention above the cure of diabetes mellitus is mentioned in Ayurveda. Ayurvedic researches undertaken during the last 50 years have not been very rewarding, except for the extremely useful exercise of literary research. Further the age of synthetic drugs comes but unfortunately, after the introduction of sulfonylurea and metformin about 50 years no major lead has been obtained in the direction of proper treatment of diabetes. This is the big question mark on synthetic drugs for answering the diabetes mellitus.
Plant extract or different folk plants preparations are being prescribed by the traditional practitioners and also accepted by the users for diabetes and other diseases in many countries especially in third world countries. Therefore, a proper scientific evaluation and searching plants by pharmacological test followed by chemical investigation is potentially necessary.
The plants drugs or extract have the marvelous efficacy to curing the diabetes and its complication without having any side effects. At present there are several Chinese traditional formulated drugs available in market but the right answer for diabetes mellitus is awaited.
According to the WHO about 65% - 80% of world population in developing counties depends on all intents and purposes on plant for their primary health care due to scarcity and lack of access to modern medicine [
As we know that India has ancient heritage of traditional medicine. In India where 75% population belong from the remote area and more than 50% of people survives below the poverty line enthusiastically use plants for the treating the diseases. During the last few decease there has been an increasing interest in the study of medicinal plant and their traditional use in different part of India.
In the recent years numbers of reports on the use of plants in traditional healing by either tribal people or indigenous communities of India is increasing [
All drugs which we have discussed in this review have a significant in their mode of action and therapy of diabetes mellitus, in contrast of plants bioactive phyto-molecules are less known about their mode of action but there is no doubt about the role of plants to treating diabetes.
It is also important to screening the world’s plant diversity extensively for more and specific bioactive phytomolecules which are helpful in treating diabetes mellitus. On the other hand the traditional formulation of antidiabetic drugs must be researched and re-standardized by using new techniques and methods for managing the diabetes mellitus. Furthermore these drugs will be accessible to the people who are unable to purchase the costly synthetic drugs. Hence herbal drugs may be an emerging alternative of synthetic drugs to curing diabetes mellitus.