Evaluation of aqueous extract of syzygium polyanthum leaves as anti-hypertensive agent in spontaneous hypertensive rat (SHR)

Hypertension is associated with significant morbidity and mortality. The use of medicinal herbs as alternative medicines to manage hypertension is increasing exponentially. Syzygium polyanthum, has been claimed traditionally as an antihypertensive agent. This study aimed to determine the antihypertensive effects of the aqueous extract of S. polyanthum (AESP) leaves and its mechanisms using spontaneously hypertensive rats (SHR). The phytochemical profiling, antioxidant properties and antihypertensive activity were evaluated. Fifty male SHR were divided equally into 5 groups; untreated-SHR, Losartan-treated, 3 groups of AESP-treated with different dosages (1500 mg/kg, 1750 mg/kg and 2250 mg/kg), and 10 male WKY rats as control. All treatments were given orally for 12th weeks. Systolic blood pressure (SBP) was measured biweekly. Whereas, the biochemical analysis, oxidative stress markers and angiotensin-converting enzyme (ACE) level were evaluated at the end of the study. The histology of thoracic aorta and kidney were assessed using haematoxylin & eosin (H&E) staining, and scanning electron microscope (SEM). AESP contains flavonoids and phenols with gallic acid detected. AESP showed high in vitro antioxidant and ACE-inhibitory activities. In AESP-treated SHR; SBP reduced significantly, improved renal function and oxidative stress markers. However, only AESP (2250 mg/kg) significantly reduced ACE concentration. There was also histology improvement of the thoracic aorta and renal in AESP-treated SHR. Hence, the study suggests that antihypertensive properties of AESP are due to its antioxidant(mainly gallic acid) and ACE inhibitory activity. Thus, this study reveals the antihypertensive mechanism of AESP exerted inhibitory activity through suppression of the ACE action which might involved RAAS pathway

Antioxidant activities of different aerial parts of putat (Barringtonia racemosa L.)

The antioxidant activities of methanolic, ethanolic and boiling water extracts of Barringtonia racemosa leaves, sticks, and barks were studied and their contents of total phenolics, flavonoids and carotenoids were measured. Methanolic extracts of aerial parts of the plant contained relatively higher levels of total phenolics than other extracts (leaf: 16.2 ± 0.02 mg gallic acid equivalent/g freeze dried-weight (FDW) tissue, stick: 29.9 ± 0.02 mg gallic acid equivalent/g FDW tissue, bark: 21.78 ± 0.20 mg gallic acid equivalent/g FDW tissue). The ethanolic extracts in aerial parts gave higher levels of total flavonoid (leaf: 38.55 ± 2.75 mg rutin/g FDW tissue, stick: 40.72 ± 5.91 mg rutin/g FDW tissue, bark: 68.29 ± 9.63 mg rutin/g FDW tissue). The amounts of β-carotene and lycopene were found higher in methanolic and ethanolic extracts of the leaf (342.2 ± 8.79 μg β-carotene/g FDW tissue, 77.38 ± 4.61μg lycopene/g freeze dried-weight tissue; 356.9 ± 0.93 μg β-carotene/g FDW tissue, 99.3 ± 5.29 μg lycopene/g FDW tissue,respectively). The methanolic and ethanolic extracts in all aerial parts tested exhibited very strong antioxidant properties when compared to butylated hydroxytoluene (BHT), ascorbic acid and α-tocopherol in the free radical scavenging and reducing power assays

The adequacy of consumer protection act 1999 in protecting consumers' rights in Malaysia over misleading and deceptive conduct / Asma’i Abdul Rauf … [et al.]

This research is a critical analysis on the adequacy of Malaysian Consumer Protection Act 1999 (CPA 1999) in governing consumers' protection. CPA 1999 was enforced on October 1999 under the Ministry of Domestic Trade, Cooperation and Consumerism in order to provide a greater protection to the consumers. Under the Act, the rights granted as the consumers cannot be taken away from consumers notwithstanding conditions in any agreement that they have signed. However, after more than 10 years of enforcement, consumers' rights are still being abused either by the traders or the consumers themselves. This led to a question where is the significant and effectiveness of the CPA 1999 of consumers' rights which are still fail to be upheld? It might be some loopholes of the said Act which make it inefficient. Thus, this study was conducted in order to examine the adequacy of the CPA 1999 in protecting consumers' rights over misleading and deceptive conduct in Malaysia

Antimicrobial and antioxidant property of Curcuma longa Linn.

Background: Curcuma longa Linn. (Zingiberaceae family) plant or turmeric is known to possess pharmacological properties at relatively nontoxic doses. The study was carried out with the aim to evaluate the antimicrobial and antioxidant activities of C. longa L.Methods: Ethanolic rhizome extract was applied against Staphylococcus aureus and Salmonella typhi using disc and well diffusion methods. Antioxidant of C. longa L. was determined by measuring 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity.Results: The ethanolic extract of rhizomes showed inhibitory activity against Gram-positive S. aureus bacteria, whereas the Gram-negative S. typhi bacteria were resistant toward the ethanol extract. Zone of inhibitions against S. aureus were 7 mm and 11 mm by disc and well method, respectively. For antioxidant activity, DPPH radical scavenging activity of ethanolic extract of C. longa L. was set against butylated hydroxytoluene (BHT). It was shown that the value of half maximal inhibitory concentration (IC50) of rhizome extract was higher than standard control. The dose response curve was utilized to determine the half maximal IC50 value for each sample. The IC50 of rhizome extract is 21.25 µg/ml, while the value IC50 for BHT is 12.42 µg/ml.Conclusions: The finding suggested turmeric rhizome-extract as a good candidate in the search for a natural antimicrobial and antioxidant agent

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

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

Acute and sub-acute antihypertensive effects of syzygium polyanthum leaf extracts with determination of gallic a using HPLC analysis

Context: Aqueous decoction of Syzygium polyanthum (ADSP) leaf is one of Malay traditionalremedial- preparations for hypertension. Intravenous ADSP reduced blood pressure of anesthetized Wistar-Kyoto (WKY) and Spontaneously-Hypertensive rats (SHR); however, acute and sub-acute effects of oral ADSP on conscious rats and its bioactive compound(s) are not comprehensively studied. This study aims to examine the acute and sub-acute effects of ADSP in comparison to methanol extract (MESP) on systolic blood pressure (SBP) of conscious WKY and SHR rats, as well as to identify their major phenolic-compound using highperformance- liquid-chromatography (HPLC). Methodology: For acute study, SHR and WKY rats were gavaged with single-dose of ADSP or MESP (2.00, 2.50 or 3.00 g/kg), vehicles, or losartan (0.01 g/kg). SBP was measured after 1, 3, 5, 6 and 24 hr-post-administration. For subacute experiment, SHR rats were gavaged once-daily with ADSP or MESP (2.50 g/kg/day), vehicles, or losartan (0.01 g/kg/day) for 3-week and their SBP was weekly-measured. Phenolic compounds were screened using ferric-chloride test, then gallic acid was determined using HPLC. Results: Acute administration of ADSP (2.50 to 3.00 g/kg) and MESP (2.00 to 3.00 g/ kg) significantly reduced SBP of SHR, but not of WKY rats. Repeated-daily-dose administration of MESP (2.5 g/kg/day) significantly reduced SBP of SHR after 2-week and sustained until 3-week, while ADSP (2.5 g/kg/day) significantly reduced SBP only after 3-week. Gallic acid was the major phenolic-compound in ADSP (157.09 ± 4.18 ppm) and MESP (134.04 ± 10.30 ppm). Conclusion: Oral ADSP and MESP that contain gallic acid possess acute and sub-acute antihypertensive effects in SHR, but MESP’s effect was more prominent than ADSP

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

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