Therapeutic effects of anthocyanin-rich Hibiscus sabdariffa L. extract on body mass index, lipid profile and fatty liver in obese-hypercholesterolaemic rat model

Background: Hibiscus sabdariffa L. or Roselle, is one of the most common flower plants cultivated worldwide. Traditionally, it is claimed to reduce weight and cholesterol level. The aim of this study was to evaluate the effects of anthocyanin-rich Roselle aqueous extract on the physical, biochemical and histological changes in obese-hypercholesterolaemic rat model.Methods: Thirty Sprague-Dawley male rats were divided into five groups (n=6 per group). Group 1 is normal control (NC) rat that was fed with normal diet. The remaining rats (Group 2-5) were fed with commercial high-fat diet (HFD) for 6 weeks to induce obese-hypercholesterolaemic (OH) rat. After induction, the OH rats were divided into 4 groups: OH-Untreated group, OH-ARTE; OH treated with 300 mg/kg Roselle aqueous (anthocyanin-rich) and 1% trifluoroacetic acid extract (ARTE), OH-Orlistat; OH treated with 37 mg/kg orlistat and OH-Atorvastatin; OH treated with 10 mg/kg atorvastatin. After the 3 weeks intervention period, all rats were sacrificed. Body mass index, lipid profile and liver enzymes were evaluated. The liver section was subjected to hematoxylin and eosin staining for histopathological evaluation.Results: This study showed that 3 weeks administration of ARTE significantly reduced BMI, improved levels of lipid profile and liver enzymes, and histopathological changes of liver when compared to OH-untreated rats. The results were also comparable to the standard drugs.Conclusions: This study suggested that Roselle extract constitutes an effective and safe alternate treatment for obesity and hyperlipidaemia

Effect of peritoneal fluid on early embryonic development

The aetiology of endometriosis associated with infertility remains poorly understood. In recent years, the potential influence of peritoneal fluid (PF) or its cellular components have been proposed as possible mediators of infertility in endometriosis through it toxic effects on pre-implantation embryo. Several factors have been identified as embryotoxic factors, however, the mechanism of embryotoxicity have not well clarified. Studies were therefore undertaken to clarify the possible mechanisms of embryotoxicity in endometriosis and to determine the possible embryotoxic factor(s) that involved in the process. The role of exogenous nutrient (pyruvate) has also been examined in reducing or eliminating the embryotoxicity. Peritoneal fluid was collected from infertile women at reproductive age with 21 endometriosis (PF-E) (7 minimal or mild, 7 moderate, 7 severe) and 7 without endometriosis (PF-NE). Addition of PF-E to the culture medium from all stages of endometriosis significantly suppressed the mouse embryo growth at all stages of development, at 24, 48 and 72 hours, which correlated with the severity of the disease, as compared to control (no peritoneal fluid). Excessive pyruvate was able to reduce the embryotoxicity at all stages of development in minimal or mild and moderate PF-E, and only during the first 24 hours in severe PF-E. The level of IL-6 concentration was significantly higher in PF-E as compared to PF-NE and correlated with the severity of the disease. However, no significant difference was noted in the level of IL-8 between the two groups. Both interleukins were found to be embryotoxic with IL-6 is more potent. A positive correlation between the levels of IL-6 and its embryotoxicity was noted. These findings propose embryotoxicity to be a possible mechanism of infertility in endometriosis and the growth promoting effects of pyruvate indicated the mechanism of embryotoxicity might involve functional disruption of the intermediary metabolism such that excessive pyruvate is required to maintain embryo growth. V

Amelioration of aorta morphology in spontaneous hypertensive rat (SHR) by syzygium polyanthum

Background: Prolonged uncontrolled hypertension can lead to vessels damage; manifested as abnormal morphology changes. Sygyzium polyanthum has been shown to has blood pressure lowering effects in SHR rats. Objective: This study was designed to evaluate the improvement effects of S. polyanthum aqueous leave extracts (AESP) on the descending thoracic aorta morphology damaged secondary to hypertension. Material & Methods: Twenty-one rats were used in this study, with 7 rats in each group. Group 1: normotensive Wistar Kyoto (WKY) rat, Group 2: untreated SHR, Group 3: SHR on AESP (2250 mg/kg). AESP was orally administered daily for 3 months. The descending thoracic aorta was harvested at the end of the study. The aorta morphology was evaluated using Hematoxylin and Eosin stain (H&E stain) and Scanning Electron Microscope (SEM). Systolic blood pressure (SBP) were also recorded every 2 weeks during the study. Results: On HE stained, treatment with AESP increased the endothelial cell lining on the surface of aortic tunica intima. The endothelial lining also notably smoother. The elastic laminae were not discontinued and more regular pattern of vascular smooth muscle cells with elongated nuclei. The thickness ratio of tunica media to tunica intima was also reduced. Under SEM, the surface of the aorta was smoother and there were no crater-like defects as compared to untreated SHR. There were also no inflammatory cells or fibrinogen seen as on the aortic surface of untreated SHR. The SBP in AESP-treated SHR was significantly reduced (107.00 + 1.68 mmHg) as compared to untreated SHR (199.75 + 2.86 mmHg, p<0.001). Conclusion: S. polyanthum improves the morphology of aorta and also significantly reduces the blood pressure

International diversification and firm's value: evidence from developing nations

Purpose: This paper aims to evaluate the impact of international diversification, through the investment abroad activities of the Malaysian multinational corporations (MNCs), on their financial performance. Design/methodology/approach: The paper applies the panel generalized method of moments (GMM) estimation technique that gives better results. Findings: The empirical findings show that the move to invest abroad has brought a positive impact on Malaysian MNCs’ financial performance. However, in terms of a firm’s risk, the results contradict the general internationalization-risk hypothesis. Research limitations/implications: The study focuses on the top 100 multinational firms; future researchers may extend the time period and use the entire sample of all the multinational firms. Practical implications: Foreign investments offer rewarding returns due to cheaper labour and raw materials, competitive edge in terms of technological advancement and larger market opportunities. Originality/value: The paper contributes to the literature using the panel GMM’s estimation that effectively control for reverse causality and serial correlation problem. The paper also contributes to the international diversification and performance relationship, in a fast-growing Malaysia

Sleep deprivation models in rodents

Sleep deprivation has been identified as a risk factor for various diseases. The number of patients suffering from sleep deprivation is increasing daily. Therefore, the risk to develop various diseases, including cardiovascular disease is increasing. However, there is a limitation to elucidate the pathophysiological changes following sleep deprivation in humans. Thus, the need arises for sleep deprivation models using animals, which will serve the purpose of understanding the disease in a better way. Several techniques have been developed to model sleep deprivation in animals, including inverted flowerpot and multiple platforms techniques. Genetic and environmental factors, costs, infrastructure and animal life spans are some of the factors that need to be considered when selecting a particular model. Furthermore, when studying sleep deprivation, tissue samples, such as peripheral blood, brain samples and aorta are used to elucidate the underlying mechanisms of a particular disease. Currently, more than ninety percent of all laboratory animal experiments are performed in rats and mice. This review article focuses on models of sleep deprivation in Rodents, which are generally used in research laboratories. The article also tries to evaluate the advantages and disadvantages of each technique discussed, guides the sleep deprivation model and helps researchers to decide on a specific model for their purpose

Syzygium polyanthum protects against hypertensive induced kidney damage in spontaneous hypertensive rat model

Syzygium polyanthum is traditionally used as anti-hypertensive agent. However, the nephroprotective effects of S. polyanthum against hypertensive induced chronic kidney disease has yet to be elucidated. This study was conducted to determine the antioxidant properties and nephroprotective effects of aqueous extract of S. polyanthum (AESP) in the spontaneous hypertensive rat model (SHR). The phytochemical constituent was identified using the phytochemical screening and HPLC methods. The in vitro antioxidant activities were determined by DPPH radical scavenging and ferric reducing antioxidant power (FRAP) assays. Fifty male SHR were equally divided into 5 groups, (n=10/group); Untreated-SHR, 20 mg/kg Losartan-treated SHR, 1500 mg/kg AESP treated SHR, 1750 mg/kg AESP treated SHR and 2250 mg/kg AESP treated SHR, while 10 male Wistar Kyoto rats (WKY) were used as control. Losartan and AESP were administered by oral gavage. Rats were sacrificed after 12 weeks of experiment. The phytochemicals include phenolics, flavonoids and alkaloids were identified. AESP has high antioxidant activity as shown by antioxidant assays. AESP normalised systolic blood pressure (p<0.05) and significantly improved renal function (p<0.05). AESP also significantly reduced malondialdehyde (MDA) (p<0.05) and increased superoxide dismutase (SOD) levels in the serum as compared to untreated-SHR group (p<0.05). Ultrastructure of renal damage improved by supplementation of AESP. Conclusively, S. polyanthum is potential to alleviate hypertensive induced chronic kidney disease through its antioxidant properties

Amelioration of aorta morphology in a spontaneous hypertensive rat (shr) by Syzygium polyanthum

Background: Prolonged uncontrolled hypertension can lead to vessels damage; manifested as abnormal morphology changes. Sygyzium polyanthum has been shown to has blood pressure lowering effects in SHR rats. Objective: This study was designed to evaluate the improvement effects of S. polyanthum aqueous leave extracts (AESP) on the descending thoracic aorta morphology damaged secondary to hypertension. Material & Methods: Twenty-one rats were used in this study, with 7 rats in each group. Group 1: normotensive Wistar Kyoto (WKY) rat, Group 2: untreated SHR, Group 3: SHR on AESP (2250 mg/kg). AESP was orally administered daily for 3 months. The descending thoracic aorta was harvested at the end of the study. The aorta morphology was evaluated using Hematoxylin and Eosin stain (H&E stain) and Scanning Electron Microscope (SEM). Systolic blood pressure (SBP) were also recorded every 2 weeks during the study. Results: On HE stained, treatment with AESP increased the endothelial cell lining on the surface of aortic tunica intima. The endothelial lining also notably smoother. The elastic laminae were not discontinued and more regular pattern of vascular smooth muscle cells with elongated nuclei. The thickness ratio of tunica media to tunica intima was also reduced. Under SEM, the surface of the aorta was smoother and there were no crater-like defects as compared to untreated SHR. There were also no inflammatory cells or fibrinogen seen as on the aortic surface of untreated SHR. The SBP in AESP-treated SHR was significantly reduced (107.00 + 1.68 mmHg) as compared to untreated SHR (199.75 + 2.86 mmHg, p<0.001). Conclusion: S. polyanthum improves the morphology of aorta and also significantly reduces the blood pressure

Tualang honey modulated nociceptive responses in the thalamus of rem sleep deprivation rat model

Sleep deprivation has been shown to alter pain responses in humans and animals. The present study investigated whether the administration of Tualang honey in the rapid eye movement (REM) sleep deprivation rat model would modulate nociceptive responses with associated changes in the thalamus. Forty-eight Sprague Dawley male rats were randomised into four groups (n=12 for each group): control group (FMC), REM sleep deprivation (REMsd), REM sleep deprivation pretreated with Tualang Honey for 1 month (REMsdH) and tank control (TC). Following sleep deprivation for 72 hours, a formalin test was conducted and pain behaviour was recorded and analysed. The rats were sacrificed, and the brains were removed for histological examination and assessment of N-methyl-D-aspartate receptor (NMDA R2) level in the thalamus. REMsdH group showed a significantly lower level of pain behaviour score and NMDA R2 compared to the REMsd group (p<0.05). In addition, REMsdH also demonstrated a significantly higher number of Nissl stained neurons in comparison with the REMsd group (p<0.05). Furthermore, dark neurons, suggestive of neuronal damage, were observed in the REMsd group. In conclusion, administration of Tualang honey before REM sleep deprivation modulated nociceptive responses and prevent changes in thalamic neurons and NMDA R2 level

Morphological evaluation of aortic vessel in Spontaneously Hypertensive Rat (SHR) Models

The spontaneously hypertensive rat (SHR) has been well established as a suitable model for hypertension research, but little is known about the morphology of hypertensive vascular remodeling in this model. The present study was designed to investigate the structural changes of blood vessels in 6 months aged SHR in comparison to their corresponding model, Wistar Kyoto rats (WKY). The study utilised 12 male rats; which were equally divided into 6 SHR and 6 WKY. During dissection, thoracic aorta was harvested for histological examination. To evaluate the morphological appearance of SHR and WKY, hematoxylin and eosin (H&E) stain was done. Whereas Scanning electron microscopy was applied to view the ultrastructure of the vessel. The result shows that the aorta histology of WKY looks normal; depicted by showing smooth intima with a single layer of endothelial cells. In contrast with SHR, the structure was slightly distorted and thicker intima observed; suggesting vascular remodeling has occurred