Gynura procumbens (Lour.) Merr (family Compositae) is cultivated in Southeast Asia, especially Indonesia, Malaysia and Thailand, for medicinal purposes. This study evaluated the in vivo hypoglycemic properties of the water extract of G. procumbens following 14 days of treatment and in vitro in RIN-5F cells. Glucose absorption from the intestines and its glucose uptake in abdominal skeletal muscle were assessed. The antidiabetic effect of water extract of G. procumbens leaves was investigated in streptozotocin-induced diabetic rats. The intraperitoneal glucose tolerance test (IPGTT) was performed in diabetic rats treated with G. procumbens water extract for 14 days. In the IPGTT, blood was collected for insulin and blood glucose measurement. After the IPGTT, the pancreases were collected for immunohistochemical study of β-cells of the islets of Langerhans. The possible antidiabetic mechanisms of G. procumbens were assessed through in vitro RIN-5F cell study, intestinal glucose absorption and glucose uptake by muscle. The results showed that G. procumbens significantly decreased blood glucose levels after 14 days of treatment and improved outcome of the IPGTT. However, G. procumbens did not show a significant effect on insulin level either in the in vivo test or the in vitro RIN-5F cell culture study. G. procumbens also showed minimal effects on β-cells of the islets of Langerhans in the pancreas. However, G. procumbens only significantly increased glucose uptake by muscle tissues. From the findings we can conclude that G. procumbens water extract exerted its hypoglycemic effect by promoting glucose uptake by muscles.
Khat (Catha edulis) as well as garlic (Allium sativum) has a potential effect on reducing the lipid contents of blood. However, a mechanism by which garlic or khat reduces plasma lipids has not been fully investigated. This study aimed to investigate the direct action of khat and/or garlic (in vitro). The effects of extracted khat and/or garlic on human blood constituents (cholesterol and triglycerides) and on vegetable oil were investigated. The results showed that aqueous garlic extract was able to form an emulsion with oil but not khat extract. Even though, either khat or garlic extract has slight effect on reducing lipid contents of blood; a higher reduction was obtained when the extracts were added in combination. The mechanism of garlic on reducing lipids could be explained by its emulsifying property, while the mechanism of khat is by lipolysis. In conclusion, the synergistic effect of garlic and khat extracts opened an interesting area for further investigation on their roles in combating cardiovascular and obesity disorders.:
Ketoprofen is a potent non-steroidal anti-inflammatory drug has been used in the treatment of various kinds of pains, inflammation and arthritis. However, oral administration of ketoprofen produces serious gastrointestinal adverse effects. One of the promising methods to overcome these adverse effects is to administer the drug through the skin. The aim of the present work is to evaluate the anti-inflammatory and analgesic effects from topically applied ketoprofen entrapped palm oil esters (POEs) based nanoemulsion and to compare with market ketoprofen product, Fastum(®) gel. The novelty of this study is, use of POEs for the oil phase of nanoemulsion. The anti-inflammatory and analgesic studies were performed on rats by carrageenan-induced rat hind paw edema test and carrageenan-induced hyperalgesia pain threshold test to compare the ketoprofen entrapped POEs based nanoemulsion formulation and market formulation. Results indicated that there are no significant different between ketoprofen entrapped POEs nanoemulsion and market formulation in carrageenan-induced rat hind paw edema study and carrageenan-induced hyperalgesia pain threshold study. However, it shows a significant different between POEs nanoemulsion formulation and control group in these studies at p<0.05. From these results it was concluded that the developed nanoemulsion have great potential for topical application of ketoprofen.
It is well established that renal sympathetic nerves are primarily involved in renal sodium and water regulation. However, the relationship between renal sympathetic nerve activity (RSNA) and renal potassium handling is not extensively known. The present study was performed to investigate the role of the renal sympathetic nervous system in the regulation of tubular potassium reabsorption and secretion.
The present investigation was carried out to evaluate the safety of standardised 50% ethanol extract of Orthosiphon stamineus plant by determining its potential toxicity after acute and subchronic administration in rats.
We assessed the role of renal sympathetic nervous system in the deterioration of renal hemodynamic and excretory functions in rats with streptozotocin (STZ)-induced diabetic kidney disease (DKD).
Preliminary investigations were carried out to evaluate the antidiabetic effects of the leaves of O. stamineus extracted serially with solvents of increasing polarity (petroleum ether, chloroform, methanol and water); bioassay-guided purification of plant extracts using the subcutaneous glucose tolerance test (SbGTT) was also carried out. Only the chloroform extract, given at 1 g/kg body weight (b.w.), significantly reduced (P < 0.05) the blood glucose level of rats loaded subcutaneously with 150 mg/kg (b.w.) glucose. The active chloroform extract of O. stamineus was separated into five fractions using a dry flash column chromatography method. Out of the five fractions tested, only chloroform fraction 2 (Cƒ2), at the dose of 1 g/kg (b.w.) significantly inhibited (P < 0.05) blood glucose levels in SbGTT. Active Cƒ2 was split into two sub-fractions Cƒ2-A and Cƒ2-B, using a dry flash column chromatography method. The activities Cƒ2-A and Cƒ2-B were investigated using SbGTT, and the active sub-fraction was then further studied for anti-diabetic effects in a streptozotocin-induced diabetic rat model. The results clearly indicate that Cƒ2-B fraction exhibited a blood glucose lowering effect in fasted treated normal rats after glucose-loading of 150 mg/kg (b.w.). In the acute streptozotocin-induced diabetic rat model, Cƒ2-B did not exhibit a hypoglycemic effect on blood glucose levels up to 7 hours after treatment. Thus, it appears that Cƒ2-B functions similarly to metformin, which has no hypoglycemic effect but demonstrates an antihyperglycemic effect only in normogycemic models. The effect of Cƒ2-B may have no direct stimulatory effects on insulin secretion or on blood glucose levels in diabetic animal models. Verification of the active compound(s) within the active fraction (Cƒ2-B) indicated the presence of terpenoids and, flavonoids, including sinensitin.
Coriolus versicolor, which is known as Yun Zhi, is one of the commonly used Chinese medicinal herbs. Recent studies have demonstrated its antitumor activities on cancer cells which led to its widespread use in cancer patient. However, little toxicological information is available regarding its safety. The present study evaluated the potential toxicity of Coriolus versicolor standardized water extract after acute and subchronic administration in rats.
As a topical delivery system, a nanoscaled emulsion is considered a good carrier of several active ingredients that convey several side effects upon oral administration, such as nonsteroidal anti-inflammatory drugs (NSAIDs).
Behavioural assessment of experimental pain is an essential method for analysing and measuring pain levels. Rodent models, which are widely used in behavioural tests, are often subject to external forces and stressful manipulations that cause variability of the parameters measured during the experiment. Therefore, these parameters may be inappropriate as indicators of pain. In this article, a stepping-force analgesimeter was designed to investigate the variations in the stepping force of rats in response to pain induction. The proposed apparatus incorporates new features, namely an infrared charge-coupled device (CCD) camera and a data acquisition system. The camera was able to capture the locomotion of the rats and synchronise the stepping force concurrently so that each step could be identified. Inter-day and intra-day precision and accuracy of each channel (there were a total of eight channels in the analgesimeter and each channel was connected to one load cell and one amplifier) were studied using different standard load weights. The validation studies for each channel also showed convincing results whereby intra-day and inter-day precision were less than 1% and accuracy was 99.36-100.36%. Consequently, an in vivo test was carried out using 16 rats (eight females and eight males). The rats were allowed to randomly walk across the sensor tunnel (the area that contained eight channels) and the stepping force and locomotion were recorded. A non-expert, but from a related research domain, was asked to differentiate the peaks of the front and hind paw, respectively. The results showed that of the total movement generated by the rats, 50.27 ± 3.90% in the case of the male rats and 62.20 ± 6.12% in that of the female rats had more than two peaks, a finding which does not substantiate the assumptions made in previous studies. This study also showed that there was a need to use the video display frame to distinguish between the front and hind paws in the case of 48.80 ± 4.01% of the male rats and 66.76 ± 5.35% of the female rats. Evidently the assumption held by current researchers regarding stepping force measurement is not realistic in terms of application, and as this study has shown, the use of a video display frame is essential for the identification of the front and hind paws through the peak signals.
The surface activity of some non-steroidal anti-inflammatory agents like ibuprofen was investigated extensively. This fact has attracted the researchers to extend this behavior to other agents like piroxicam. Piroxicam molecules are expected to orient at the interface of oil and aqueous phase. The aim of this study was, firstly, to assess the surface and interfacial tension behaviour of newly synthesised palm oil esters and various pH phosphate buffers. Furthermore, the surface and interfacial tension activity of piroxicam was studied. All the measurements of surface and interfacial tension were made using the tensiometer. The study revealed that piroxicam has no effect on surface tension values of all pH phosphate buffers and palm oil esters. Similarly, various concentrations of piroxicam did not affect the interfacial tensions between the oil phase and the buffer phases. Accordingly, the interfacial tension values of all mixtures of oil and phosphate buffers were considerably high which indicates the immiscibility. It could be concluded that piroxicam has no surface activity. Additionally, there is no surface pressure activity of piroxicam at the interface of plam oil esters and phosphate buffers in the presence of Tweens and Spans.
Recently, the fruits of Hylocereus polyrhizus, known as red dragon fruit, have received much attention from growers worldwide. However, there is little toxicological information regarding the safety of repeated exposure to these fruits. The present study evaluated the potential toxicity of a methanol extract of H. polyrhizus fruit after acute and subchronic administration in rats. In the acute toxicity study, single doses of fruit extract (1250, 2500 and 5000 mg/kg) were administered to rats by oral gavage, and the rats were then monitored for 14 days. In the subchronic toxicity study, the fruit extract was administered orally to rats at doses of 1250, 2500 and 5000 mg/kg/day for 28 days. There was no mortality or signs of acute or subchronic toxicity. There was no significant difference in body weight, relative organ weight or hematological parameters in the subchronic toxicity study. Biochemical analysis showed some significant changes, including creatinine, globulin, total protein and urea levels. No abnormality of internal organs was observed between treatment and control groups. The lethal oral dose of the fruit extract is more than 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 5000 mg/kg per day for 28 days.
This study evaluated the anti-inflammatory effect of Kaempferia galanga (KG) using an activity-guided approach. KG rhizomes were serially extracted with petroleum ether, chloroform, methanol and water. These extracts (2 g/kg each) were tested for their ability to inhibit carrageenan-induced rat paw edema. The chloroform extract was found to exert the highest inhibition (42.9%) compared to control (p < 0.001), hence it was further fractionated by washing serially with hexane, hexane-chloroform (1:1) and chloroform. The chloroform fraction (1 g/kg) showed the highest inhibitory effect (51.9%, (p < 0.001), on carrageenan-induced edema. This chloroform fraction was further fractionated with hexane-chloroform (1:3) and chloroform, and of the two fractions, the hexane-chloroform sub-fraction was the most effective in inhibiting edema (53.7%, p < 0.001). GC-MS analysis of the active sub-fraction identified ethyl-p-methoxycinnamate (EPMC) as the major component, which was re-crystallized. EPMC dose-dependently inhibited carrageenan-induced edema with an MIC of 100 mg/kg. Moreover, in an in vitro study, EPMC non-selectively inhibited the activities of cyclooxygenases 1 and 2, with IC₅₀ values of 1.12 µM and 0.83 µM respectively. These results validate the anti-inflammatory activity of KG which may be exerted by the inhibition of cyclooxygenases 1 and 2. EPMC isolated from this plant may be the active anti-inflammatory agent.
Orthosiphon stamineus Benth. (Lambiaceae) is an important plant in traditional folk medicine. This review is a comprehensive summary of the currently available chemical, pharmacological, and toxicological investigations as well as the traditional and therapeutic uses of this plant. Different in vitro and in vivo models have been addressed along with a survey of all phytochemicals identified in this plant, including flavonoids, terpenoids, and essential oils. Previous studies revealed that O. stamineus possesses several pharmacological activities, which are attributed to its phytochemical content. It was found that O. stamineus exhibits diuretic, hypouricemic, renal protective, antioxidant, anti-inflammatory, hepatoprotective, gastroprotective, antihypertensive, antidiabetic, antihyperlipidemic, antimicrobial, and anorexic activities. In conclusion, O. stamineus has wide traditional and pharmacological uses in various pathophysiological conditions. Therefore, it is an attractive subject for further experimental and clinical investigations.
Orthosiphon stamineus extracts contain three flavonoids (3'-hydroxy-5,6,7,4'-tetramethoxyflavone, sinensetin, and eupatorin) as bioactive substances. Previous reported high performance liquid chromatography- ultraviolet (HPLC-UV) methods for the determination of these flavonoids have several disadvantages, including unsatisfactory separation times and not being well validated according to International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) standard guidelines. A rapid, specific reversed-phase HPLC method with isocratic elution of acetonitrile: isopropyl alcohol: 20mM phosphate buffer (NaH(2)PO(4)) (30:15:55, v/v) (pH 3.5) at a flow-rate of 1ml/minute, a column temperature of 25°C, and ultraviolet (UV) detection at 340 nm was developed. The method was validated and applied for quantification of different types of O stamineus extracts and fractions. The method allowed simultaneous determination of 3'-hydroxy-5,6,7,4'-tetramethoxyflavone, sinensetin, and eupatorin in the concentration range of 0.03052-250 μg/ml. The limits of detection and quantification, respectively, were 0.0076 and 0.061 μg/ml for 3'-hydroxy-5,6,7,4'-tetramethoxyflavone, 0.0153 and 0.122 μg/ml for sinensetin and 0.0305 and 0.122 μg/ml for eupatorin. The percent relative standard deviation (% RSD) values for intraday were 0.048-0.368, 0.025-0.135, and 0.05-0.476 for 3'-hydroxy-5,6,7,4'-tetramethoxyflavone, sinensetin, and eupatorin, respectively, and those for intraday precision were 0.333-1.688, 0.722-1.055, and 0.548-1.819, respectively. The accuracy for intraday were 91.25%-103.38%, 94.32%-109.56%, and 92.85%-109.70% for 3'-hydroxy-5,6,7,4'-tetramethoxyflavone, sinensetin, and eupatorin, respectively, and those for interday accuracy were 97.49%-103.92%, 103.58%-104.57%, and 103.9%-105.33%, respectively. The method was found to be simple, accurate and precise and is recommended for routine quality control analysis of O stamineus extract containing the three flavonoids as the principle components in the extract.
The involvement of interleukin-18 (IL-18) and the effects of modulating its release on the course of malaria infection were investigated using Plasmodium berghei ANKA infection in ICR mice as a model. Results demonstrated that plasma IL-18 concentrations in malarial mice were significantly elevated and positively correlated with the percentage parasitaemia development. Significant expressions of IL-18 were also observed in the brain, spleen and liver tissues. Slower development of parasitaemia was observed significantly upon inhibition and neutralization of IL-18, whereas faster development of parasitaemia was recorded when the circulating levels of IL-18 were further augmented during the infection. Inhibition and neutralization of IL-18 production also resulted in a significant decrease of plasma concentrations of pro-inflammatory cytokines (TNFα, IFNγ, IL-1α and IL-6), whereas the anti-inflammatory cytokine, IL-10, was significantly increased. Augmenting the release of IL- 18 during the infection on the other hand resulted in the opposite. Early mortality in malarial mice was also observed when the circulating levels of IL-18 were further augmented. Results proved the important role of IL-18 in immune response against malaria and suggest that IL-8 is pro-inflammatory in nature and may involve in mediating the severity of the infection through a pathway of elevating the pro-inflammatory cytokine and limiting the release of anti-inflammatory cytokine.
In the present study, we tested a 50% ethanolic extract of Orthosiphon stamineus plants and its isolated bioactive compound with respect to their α-glucosidase and α-amylase inhibitory activities.
The stepping forces of normal and Freund Complete Adjuvant (FCA)-induced arthritic rats were studied in vivo using a proposed novel analgesic meter. An infrared charge-coupled device (CCD) camera and a data acquisition system were incorporated into the analgesic meter to determine and measure the weight of loads on the right hind paw before and after induction of arthritis by FCA injection into the paw cavity. FCA injection resulted in a significant reduction in the stepping force of the affected hind paw. The stepping force decreased to the minimum level on day 4 after the injection and then gradually increased up to day 25. Oral administration of prednisolone significantly increased the stepping forces of FCA-induced arthritic rats on days 14 and 21. These results suggest that the novel device is an effective tool for measuring the arthritic pain in in vivo studies even though walking is a dynamic condition.
Animal models with various combination of host-parasite have long been employed to study malaria pathogenesis. Here, we describe the combination of Plasmodium berghei ANKA infection in inbred ICR mice as a model of cerebral malaria (CM).
Orthosiphon stamineus is a popular folk medicine widely used to treat many diseases including diabetes. Previous studies have shown that the sub-fraction of chloroform extract was able to inhibit the rise of blood glucose levels in a glucose tolerance test. This study was carried out to evaluate the chronic effect and possible mechanism of action of the bioactive chloroform sub-fraction of O. stamineus using streptozotocin-induced diabetic rats and in vitro methods. Administration of the chloroform extract sub-fraction 2 (Cƒ2-b) at a dose of 1 g/kg twice daily on diabetic rats for 14 days showed a significant lowering (p < 0.05) of the final blood glucose level compared to the pretreatment level. However, there were no significant differences in the plasma insulin levels post-treatment compared to the pretreatment levels for all doses of Cƒ2-b. Conversely, Cƒ2-b at a concentration of 2 mg/mL significantly increased (p < 0.001) the glucose uptake by the rat diaphragm muscle. The increase in glucose uptake was also shown when the muscle was incubated in a solution containing 1 IU/mL of insulin or 1 mg/mL of metformin. Furthermore, the effect of this sub-fraction on glucose absorption in the everted rat jejunum showed that Cƒ2-b at concentrations of 0.5 mg/mL, 1 mg/mL and, 2 mg/mL significantly reduced the glucose absorption of the jejunum (p < 0.05-0.001). Similarly, the absorption of glucose was also inhibited by 1 mg/mL and 2 mg/mL of metformin (p < 0.001). These results suggest that the effect of Cƒ2-b may be due to extra-pancreatic mechanisms. There was no evidence that the plant extract stimulated the release of insulin in order to lower the blood glucose level.