“COMBINED EFFECT OFMOMORDICA CHARANTIAFRUIT EXTRACT WITH ORAL HYPOGLYCEMICS IN DIABETIC NEUROPATHIC PAIN”.
a)BRIEF RESUME OF THE INTENDED WORK:
6.1 Need of study:
Diabetes mellitus (DM) is one of the most common chronic medical conditions affecting over 100 million people world-wide1. Diabetic neuropathy is the most common complication of diabetes reaching 45–50% prevalence compared to 25–30% of retinopathy and 20% of nephropathy2. Diabetic neuropathy has been defined as presence of symptoms and/or signs of peripheral nerve dysfunction in diabetics after exclusion of other causes3. It is mostly characterized by pain that can occur spontaneously as a result of exposure to mild painful stimuli, i.e., hyperalgesia4. Diabetic neuropathic patient generally complain about persistent burning or tingling sensation, usually in the legs and feet and inability to detect heat and cold, cutaneoushyperaesthesia, loss of vibration sensation and paradoxically and loss of pain perception5. It affects patients with both Type 1 and 2 DM with Poor blood glucose control is a prominent risk factor6. Hyperglycemia induced oxidative stress contributes to the etiology of nerve dysfunction. Reactive oxygen species (ROS) cause vascular endothelium dysfunction which reduces nitric oxide (NO) mediated vasodilatation and increases local vasoconstrictor production which reduces nerve perfusion, causing endoneural hypoxia which results in conduction deficits 5-7.
Any agent which can scavenge reactive oxygen species can be used as powerful analgesic drug for neuropathic pain8. Neuropathic pain is refractory to treatment with conventional analgesics such as opiates and non-steroidal anti-inflammatory drugs9-10 as well as antidepressant agents MOMORDICA CHARANTIA is traditionally known for its medicinal properties such as antidiabetic anticancer MOMORDICA CHARANTIA fruit has shown some other activities like gout, rheumatism and subacute cases of the spleen and liver diseases, malaria, colic, sores and wounds, infections, worms and parasites, as an emmenogogue, and for measles, hepatitis,and fevers.Fruit pulp, leaf juice and seeds show antihelimintic effect11. Despite considerable progress in the treatment of diabetes by oral hypoglycaemic agents, search for newer drugs continues because the existing synthetic drugs have several limitations .The herbal drugs with antidiabetic activity are yet to be commercially formulated as modernmedicines, even though they have been acclaimed for their therapeutic properties inthe traditional systems of medicine.Hence the present study is necessary to evaluate the role of MOMORDICA CHARANTIA fruitextract in combination with oral hypoglycemic agents in the treatment of peripheral diabetic neuropathic pain in rats.
6.2 Review of Literature
MOMORDICA CHARANTIAis a member of Cucurbitaceae, commonly known as kugua, karela, bittergourd or bitter melon. It is the most popular herbal resource (Marles and Farnsworth, 1995) and is often used to treat diabetes (Arvigo and Balick, 1993). The anti-diabetic potential of MOMORDICA CHARANTIAis well established in streptozocin- or alloxan-induced diabetic rats, mice and rabbit (Akhtar et al., 1981; Sarkar et al., 1996; Kar et al., 2003), genetically diabetic mice (Miura et al., 2001) and in humans with Type 2 diabetes (Srivastava et al., 1993).(reference 13)
The hypoglycemic potential of MOMORDICA CHARANTIAin thepresent study could be explained by the mechanisms previouslydescribed by several authors in a diabetic animal model(Welihinda and Karunanayake, 1986; Welihinda et al., 1986;Ahmed et al., 1998). As such, MOMORDICA CHARANTIAincreasesthe renewal of β-cells in the pancreas or may permit therecovery of partially destroyed β-cells (Ahmed et al., 1998)and stimulates pancreatic insulin secretion (Welihinda et al.,1982). These could likely explain the significant increase inthe plasma insulin level when streptozocin-induced diabeticrats were treated with MOMORDICA CHARANTIA (Sharma et al.,1995). Furthermore, MOMORDICA CHARANTIAdisplays insulin-likeproperties (Ng et al., 1986), remarkably stimulates glycogenstorage by the liver (Welihinda et al., 1986) and improves peripheralglucose uptake (Welihinda and Karunanayake, 1986).(reference 13)
Karela fruit extract has been shown to have, besides hypoglycemic properties, strong hypolipidemic action on diabetic hyperglyceridemia and hypercholesterolemia as well. In addition, it also has some antioxidative properties , which may contribute towards preventing lipid peroxidative damage.(reference 12)
Administration of MOMORDICA CHARANTIA to STZdiabeticrats, decreases blood glucose levels. Thishypoglycaemiceffect may be due to depression of keygluconeogenic enzymes or the increase in the levels ofglucose transporters and stimulation of glucose uptake inskeletal muscle cells. Another effect of this plant is topreserve the islet β cell and β cells functions, which resultin a significant increase in insulin secretory activity. Inaddition, the administration of MOMORDICA CHARANTIA fruit juice is effective in reducing systolic blood pressure..(reference 16)
6.3 Objective of study:
The objectiveof the present study is to evaluate the antinociceptive action ofMOMORDICA CHARANTIAfruit extractand to delineate its possible adjuvant in diabetic neuropathic pain therapy.
SPECIFIC OBJECTIVES:
Primary outcome
- To study the role of fruit extract of MOMORDICA CHARANTIAin diabetic neuropathic pain.
- To study whether oral hypoglycemics can play a vital role in diabetic neuropathic pain.
- To study the effect of the fruit extraMOMORDICA CHARANTIAin combination with standard oral hypoglycemic agents in diabetic neuropathic pain.
To study the effect of fruit extract of MOMORDICA CHARANTIAalone and in combination with oral hypoglycemic agents on structural integrity of the sciatic nerve.
b)MATERIALS AND METHODS:
7.1 Source of Data:
Data will be obtained from CD-Rom, Internet facilities, Literatures and related articles from libraries of Krupanidhi College of Pharmacy, Indian Institute of Sciences, Government College of Pharmacy etc., and other Research Publications and Journals
7.2 Method of Collection of Data:
MOMORDICA CHARANTIA extraction:
Solvent extraction:
One gram of the finely ground sample was weighed into a test tube and 10 ml methanol was added and the sample was then extracted for 2 h in an ultrasonic bath at 65 °C. After extraction, the sample was cooled to room temperature and then centrifuged at 1500 rpm for 15min.(reference 15)
An authentic standardized MC Extract’s will be obtained fromPhytotech Extracts Pvt. Ltd., Bangalore, India. The preparation has been standardised and optimised at the commercial plant ofPhytotechExtracts Pvt. Ltd., Bangalore, India.
EXPERIMENTAL MODELS:
Source of animals : Sprague Dawley rats will be obtained from animal house of Krupanidhi college of pharmacy (in-bred animals)
- Oral glucose tolerance test17:
Group 1: Normal control, rats receive saline/vehicle.
Group 2: Diabetic control.
Group 3: MOMORDICA CHARANTIA(500 mg/kg).(reference 14)
Group 4: Pioglitazone (10 mg/kg).
Group 5: Glipizide (5mg/kg).
Glucose will be fed 30 min and 1hr after the administration of extracts. Blood will be withdrawn from the retro orbital sinus under ether inhalation at 0, 30, 60, 90 and 120 min of glucose administration. Glucose levelswill be estimated.
2. Single and multiple dose study in normal and diabetic rats.18
Single dose study: Normal and diabetic rats were administered with a single dose of oral hypoglycemic agents and MOMORDICA CHARANTIAfruit extract. The blood glucose level were estimated just prior to extract oralhypoglycaemic agents(OHA) administration and at 1, 2 and 4 h after administration. Glucose levels were estimated by using glucose diagnostic kit.
Multiple dose study: The same groups (Single dose study) of normal and diabetic animals were continued with the same dose levels of MOMORDICA CHARANTIAfruit extract and OHA once daily, for 11 days. The glucose levels of all the animals were measured on 3, 5, 7, 9 and 11th day of the treatment period.
3.Development of high fat diet-fed/low dose streptozotocin treated type 2 diabetic rats19.
The animals were fed high fat diet(HFD),once a day for 2 weeks followed by i.p injection of streptozotocin(35mg/kg) dissolved in 1M/l citrate buffer (pH4.4) after overnight fasting. The rats with non fasting plasma glucose level of >300 mg/dl were considered diabetic. Blood sample was collected from tail vein and glucose was measured using glucose diagnostic kit (Accucheck, India)19.
4.Effect of Momordicacharatia extract alone and in combination with oral hypoglycemic agents in streptozotocin induced diabetic rats (8-10 animals in each group):
Group 1: Normal control, rats receive saline/vehicle.
Group 2: Diabetic control.
Group 3: Diabetic rats treated with MOMORDICA CHARANTIAextract.
Group 4: Diabetic rats treated with Pioglitazone.
Group 5: Diabetic rats treated with glipizide.
Group 6: Diabetic rats treated with pioglitazone plus glipizide.
Group 7: Diabetic rats treated with MOMORDICA CHARANTIAfruit extract plus
pioglitazone (low dose).
Group8: Diabetic rats treated with MOMORDICA CHARANTIAextract plus
Glipizide (low dose)
At the end of the treatment period (8-10 weeks) the rats will be sacrificed by decapitation and the sciatic nerve will be excised and histopathological studies will be carried out19.
5. TREATMENT PROTOCOL
A. Induction and assessment of diabetic induced neuropathy in rats.
B. The following diabetic neuropathic animal models19will be used to evaluate the
antinociceptive effect MOMORDICA CHARANTIAfruit extract.
- Thermal stimuli : Tail immersion (warm water) test / Hot plate test.
- Chemical stimuli: Formaldehyde solution testing.
7.3 Does the study require any investigation or interventions to be conducted on patients or the human or animals? If so please describe briefly:
YES
Study requires investigation on animals. The effects of the drug will be studied on various parameters using rats as experimental animal model.
7.4 Has ethical clearance been obtained from your institute
Ethical Committee approval letter is enclosed.
c)List of references:
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- Vijan S, Stevens LD, Herman HW, Funnell MM, Standiford JC. Screening, Prevention,Counseling and Treatment for complication of Type 2 Diabetes Mellitus. J Gen intern Med 1997;12:567-580.
- Brown MJ, Asbury AK. Diabetic neuropathy. Ann Neurol 1984;15:02-12.
- Vandam PS. Oxidative stress and diabetic neuropathy: Pathophysiology mechanism and treatment perspectives. Diabetes/MetabRes. Rev 2002;18:176-184.
- Said G. Diabetic neuropathy: an update. J neurol 1996;243:431-440.
- Vincent AM, Russell JW, Low P, Feldman EL. Oxidative stress in the pathogenesis of diabetic neuropathy. Endocr. Rev 2004;25:612-628.
- Chan EC, Pannangpetch P, Woodman OL. Relaxation to flavones and flavonols in ratisolated thoracic aorta: Mechanism of action and structure activity relationship. JCardiovascPharmacol2000;35:326-333.
- Clark CMJR, Lee DA. Prevention and treatment of the complication of diabetes mellitus. N Engl J Med 1995;332:1210-1217.
- Arner S, Meyerson BA. Lack of analgesic effect of opioids on neuropathic and idiopathic forms of pain. Pain 1988;33:11-23.
- Tanelian DL, Brose WG. Neuropathic pain can be relieved by drugs that are use- dependent sodium channel blocker Lidocaine, carbamazepine and mexiletine. Anesthesiology 1991;74:26-71.
- D. Sathish Kumar, K. VamshiSharathnath, P. Yogeswaran, A. Harani, K. Sudhakar, P. Sudha et al. a medicinal potency of momordicacharantiaInternational Journal of Pharmaceutical Sciences Review and Research.2010;vol(1):95
- I. Ahmed, M. S. Lakhani, M. Gillett, A. John, H. Raza.Hypotriglyceridemic and HypocholesterollemicEfffects of AntidiabeticMomordicacharantia(Karela) Fruit Extract in Streptozotocin-Induced Diabetic Rats. Diabetes Research and Clinical Practice. 2001;vol(51):155-161.
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diabetic rats . Journal of Ethnopharmacology 2006;vol(105):196-200.
- Susan Nancy Nivitabishekam, Mohammed Asad, V. Satya Prasad.Pharmacodynamic interaction ofMomordicacharantiawith rosiglitazone in rats.journal homepage 2009; vol(177):247-253 .available from url
- Budrat P,Shotipruk A. Extraction of Phenolic Compounds from Fruits of Bitter Melon (Momordicacharantia) with Subcritical Water Extraction and Antioxidant Activities of These Extracts. Available from .
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GarugapinnataRox in streptozotocin-nicotinamide induced type-II diabetes
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fenugreek seeds extract is sustainable and mediated, in part, by the activation of hepatic enzymes. Phytother Res 2008;22:500-505.
19. Kumar NP, Annamalai AR, Thakur RS. Antinociceptive property of EmbelicaOfficinalisGaertan (amla) in High fat diet fed/low dose streptozotocin induced diabetic neuropathy in rats. Indian J Exp Biol 2009;47:737-742.