Platelet augmentation activity of mature leaf juice of Sri Lankan wild type cultivar of Carica papaya L: Insights into potential cellular mechanisms.

ETHNOPHARMACOLOGICAL RELEVANCE: Carica papaya L., a common fruit crop of the family Caricaceae and its leaf juice/extract is a traditionally commended preparation against dengue and other thrombocytopenic diseases by many Asian countries. AIM OF THE STUDY: The present study posits the potential cellular mechanisms of platelet augmentation activity of mature leaf juice of Sri Lankan wild-type Carica papaya. MATERIALS AND METHODS: C. papaya leaf juice prepared from different cultivar types, maturity of the leaf, agro-climatic region, and preparation methods were orally administered to hydroxyurea-induced thrombocytopenic rats at 0.72 ml/100 g BW dosage to investigate the most potent platelet increasing preparation. The papaya juice doses; low dose (LD-0.18 ml/100 g BW), human equivalent dose (HED-0.36 ml/100 g BW), and high dose (HD-0.72 ml/100 g BW), were administered to thrombocytopenic rats (N = 6/group) daily for three consecutive days and post-treatment plasma levels of interleukin 6 (IL-6), thrombopoietin (TPO), and platelet-activating factor (PAF) were quantified using specific rat ELISA kits. The mature leaf juice of C. papaya induced IL-6 secretion from bone marrow cell (BMC) cultures was quantified using ELISA. The ability of papaya juice to protect the platelet membrane, from the damage caused by the lytic agent was analyzed in vitro using the lactate dehydrogenase (LDH) assay. The effect of the mature leaf juice of C. papaya on secondary hemostasis was investigated using blood coagulation and clot hydrolyzing activity. RESULTS: The comparative analysis revealed that the platelet increasing activity of C. papaya leaf did not significantly differ among different types of cultivar, maturity of the leaf, agro-climatic regions and preparation methods (p > 0.05). Both TPO and PAF levels in thrombocytopenic rats diminished when treated with all three doses of the mature leaf juice of C. papaya (p < 0.05), yet IL-6 plasma level was unaltered (p > 0.05). Nevertheless, ex vivo treatment of the mature leaf juice of C. papaya had significantly enhanced IL-6 levels of rat BMC cultures (p < 0.05). Pre-treatment of platelets with the mature leaf juice of C. papaya at different concentrations significantly inhibited LDH leakage from platelets and may have reduced the membrane damage caused by the lytic agent (p < 0.05). Treatment of mature leaf juice of C. papaya also significantly reduced blood clotting time through the extrinsic pathway of the blood coagulation cascade (p < 0.05). Further, prolonged incubation of the plasma clot with different concentrations of the papaya leaf juice revealed dose-dependent hydrolysis of the blood clot, indicating fibrinolysis activity. CONCLUSIONS: The current study exceeded the traditional medicinal claims, and scientifically affirmed the platelet augmentation activity of mature leaf juice of C. papaya. The mechanistic rationale tested herein explicated that the platelet augmentation activity of the papaya leaf juice can be partially attributed to the stimulation of bone marrow megakaryocytes via modulating thrombopoietic cytokines TPO and IL-6, and by inhibiting the secretion of PAF, while reducing the peripheral platelet destruction by stabilizing the platelet membrane. Further, mature leaf juice of C. papaya imparted both pro-coagulation and fibrinolysis activity of secondary hemostasis endorsing its potential against thrombocytopenia.

Cinnamomum zeylanicum (Ceylon cinnamon) as a potential pharmaceutical agent for type-2 diabetes mellitus: study protocol for a randomized controlled trial.

BACKGROUND: Previous studies have explored the anti-diabetic effects of Cinnamomum cassia extract in vivo and in vitro. However, there are no studies at present exploring the effects of the indigenous species of Sri Lankan cinnamon (Cinnamomum zeylanicum) in patients with diabetes mellitus. The present study aims to evaluate the potential effects of Cinnamomum zeylanicum extract as a pharmaceutical agent in patients with type-2 diabetes mellitus. METHODS/DESIGN: The study will be conducted as a randomized, double-blind, placebo-controlled clinical trial for a period of 4 months at the Medical Clinic, University Medical Unit, National Hospital of Sri Lanka. A total of 210 subjects with diabetes, in three equal groups, will be recruited for the study. The patients will be randomized in a 1:1:1 ratio according to the method of block randomization and the subjects will be randomly and equally assigned into two test groups (n = 70 each) and one placebo group (n = 70). The population will be stratified at randomization based on age, gender and disease severity. The treatment drug is a capsule containing Cinnamomum zeylanicum extract as the active ingredient and the placebo capsule will contain lactose monohydrate. Two doses of Cinnamomum zeylanicum extracts (250 mg and 500 mg of the cinnamon extract) will be used. The study drugs will be double blinded to both investigators and participants. The visits and the evaluations will be done as follows: screening (visit 0), 1 month (visit 1), 2 months (visit 2), 3 months (visit 3) and 4 months (visit 4). The following primary outcome measures will be evaluated: glycosylated hemoglobin (HbA1c), fasting plasma glucose (FPG) and serum insulin. Secondary outcome measures include: Body Mass Index (BMI) and other anthropometric parameters, blood pressure, total cholesterol, low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL) and triglycerides (TAG). Data will be analyzed using SPSS version 14. DISCUSSION: We describe the protocol for a clinical trial design evaluating the effects of Cinnamomum zeylanicum (Ceylon cinnamon) in patients with type-2 diabetes mellitus. The result of the present study, positive or negative, should provide a step change in the evidence guiding current and future policies regarding the use of cinnamon dietary supplementation in patients with diabetes. TRIAL REGISTRATION: Sri Lanka Clinical Trials Registry (SLCTR), identifier: SLCTR/2017/010 ( http://slctr.lk/trials/714 ). Registered on 5 April 2017; study protocol version 3.1 21 March 2017.

Artemisia vulgaris L. ethanolic leaf extract reverses thrombocytopenia/thrombocytosis and averts end-stage disease of experimental severe Plasmodium berghei murine malaria.

BACKGROUND & OBJECTIVES: Artemisinin isolated from Artemisia annua is the most potent antimalarial against chloroquine resistant Plasmodium falciparum malaria. We previously reported that the ethanolic leaf extract of Artemisia vulgaris, an invasive weed and the only Artemisia species in Sri Lanka, possess both potent and safe antimalarial activity (in terms of antiparasitic properties) in a P. berghei murine malaria model. We report here a prototype study that investigated antidisease activities of A. vulgaris ethanolic leaf extract (AVELE) in a P. berghei ANKA murine malaria model that elicit pathogenesis similar to falciparum malaria. Profound thrombocytosis and thrombocytopenia in mice were detected in early-stage (Day 3), and at a later stage of infection (Day 6), respectively. Plasmodium berghei infected mice, 7 or 8 days post-infection reached end-stage disease with rapid drop in body temperature and usually die within 24 h, as a consequence of cerebral malaria. METHODS: Three doses of the AVELE (500, 750 and 1000 mg/kg) were used to assess antidisease activity of A. vulgaris in terms of survival, effects on thrombocyte related pathology and end-stage disease, antipyretic activity, and antinociception, using standard methodology. RESULTS: The 1000 mg/kg dose of AVELE significantly increased survival, reversed the profound thrombocytopenia/ thrombocytosis (p ≤0.01), altered the end-stage disease (p ≤0.05), and manifested significant antipyretic and antinociceptive (p ≤0.05) activities. INTERPRETATION & CONCLUSION: We conclude that a crude ethanolic leaf extract of A. vulgaris, showed potent antimalarial properties, in terms of antidisease activities; antipyretic activity, peripheral and central antinociception, increased survival, averted end-stage disease and reversed thrombocytopenia/thrombocytosis.

Antimalarial properties of Artemisia vulgaris L. ethanolic leaf extract in a Plasmodium berghei murine malaria model.

BACKGROUND & OBJECTIVES: Artemisinin isolated from Artemisia annua is the most potent antimalarial drug against chloroquine-resistant Plasmodium falciparum malaria. Artemisia vulgaris, an invasive weed, is the only Artemisia species available in Sri Lanka. A pilot study was undertaken to investigate the antiparasitic activity of an A. vulgaris ethanolic leaf extract (AVELE) in a P. berghei ANKA murine malaria model that elicits pathogenesis similar to falciparum malaria. METHODS: A 4-day suppressive and the curative assays determined the antiparasitic activity of AVELE using four doses (250, 500, 750 and 1000 mg/kg), Coartem® as the positive control and 5% ethanol as the negative control in male ICR mice infected with P. berghei. RESULTS: The 500, 750 and 1000 mg/kg doses of AVELE significantly (p ≤ 0.01) inhibited parasitaemia by 79.3, 79.6 and 87.3% respectively, in the 4-day suppressive assay, but not in the curative assay. Chronic administration of the high dose of AVELE ruled out overt signs of toxicity and stress as well as hepatotoxicity, renotoxicity and haematotoxicity. INTERPRETATION & CONCLUSION: The oral administration of a crude ethonolic leaf extract of A. vulgaris is non-toxic and possesses potent antimalarial properties in terms of antiparasitic activity.

Effects of Cinnamomum zeylanicum (Ceylon cinnamon) on blood glucose and lipids in a diabetic and healthy rat model.

OBJECTIVES: To evaluate short- and long-term effects of Cinnamomum zeylanicum on food consumption, body weight, glycemic control, and lipids in healthy and diabetes-induced rats. MATERIALS AND METHODS: The study was conducted in two phases (Phase I and Phase II), using Sprague-Dawley rats in four groups. Phase I evaluated acute effects on fasting blood glucose (FBG) (Groups 1 and 2) and on post-oral glucose (Groups 3 and 4) blood glucose. Groups 1 and 3 received distilled-water and Groups 2 and 4 received cinnamon-extracts. Phase II evaluated effects on food consumption, body weight, blood glucose, and lipids over 1 month. Group A (n = 8, distilled-water) and Group B (n = 8, cinnamon-extracts) were healthy rats, while Group C (n = 5, distilled-water) and Group D (n = 5, cinnamon-extracts) were diabetes-induced rats. Serum lipid profile and HbA1c were measured on D-0 and D-30. FBG, 2-h post-prandial blood glucose, body weight, and food consumption were measured on every fifth day. PHASE I: There was no significant difference in serial blood glucose values in cinnamon-treated group from time 0 (P > 0.05). Following oral glucose, the cinnamon group demonstrated a faster decline in blood glucose compared to controls (P < 0.05). Phase II: Between D0 and D30, the difference in food consumption was shown only in diabetes-induced rats (P < 0.001). Similarly, the significant difference following cinnamon-extracts in FBG and 2-h post-prandial blood glucose from D0 to D30 was shown only in diabetes-induced rats. In cinnamon-extracts administered groups, total and LDL cholesterol levels were lower on D30 in both healthy and diabetes-induced animals (P < 0.001). CONCLUSIONS: C. zeylanicum lowered blood glucose, reduced food intake, and improved lipid parameters in diabetes-induced rats.

Comparative powder microscopy of Alpinia calcarata Roscoe and Alpinia galanga (Linn.) Willd.

Medicinal plant materials are being adulterated in commerce due to many reasons such as similar morphological features, same name as written in classical text, presence of similar active principles in the substituted plant etc., that may badly affect the therapeutic activity of the finished products. Therefore, systematic identification is becoming essential in order to produce standardized finished herbal products. The present study includes two medicinal plant rhizomes; Alpinia calcarata Roscoe (Heenaratta) and A. galanga (Linn.) Willd (Aratta) whose microscopical build up was different from each other and was assessed by standard Pharmacognostical methods. Diagnostic identification characters of A. calcarata were compound starch grins, triangular-shaped starch grains, and plenty of simple starch grains in one parenchyma cell compared to that of A. galanga. Diamond-shaped silica crystals were found only on A. galanga rhizome powder. Present study has revealed an easy technique to identify two similar medicinal plant materials microscopically and this method can also be employed to detect the degree of adulteration in powdered raw medicinal plant materials as well.