Search

Nicotine use disorders, which are typically acquired through tobacco smoking, are a global problem and a leading cause of preventable deaths. Unfortunately, the available therapies intended for tobacco smoking cessation have varying efficacy among smokers in addition to some adverse effects observed. These factors, alongside the cost of such therapies deemed as a financial burden by some, contribute to the failure to meet patients' needs. This necessitates the many studies being conducted on the possible use of natural products in the treatment of nicotine use disorders to address such issues. Therefore, this review aims to discuss published data documenting the effects of plant extracts and bioactive compounds on nicotine-induced reactions and nicotine use disorders by looking into the different effects, possible mechanisms, and the putative targets of these selected natural products. A total of 21 natural products and bioactive compounds were obtained from searches across PubMed, Ovid Medline and Scopus databases which comprised of studies performed in vitro and in vivo as well as human trials. These data suggest that these natural products may have the potential to be utilized to treat nicotine use disorders. Undoubtedly, more detailed studies are still required to resolve conflicting or inconclusive outcomes from these investigations before clinical use is warranted. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the blood pressure-lowering effect of green tea (GT) extract alone and in combination with an angiotensin converting enzyme (ACE) inhibitor, perindopril, on rats. Methods: The study consisted of four groups of five spontaneously hypertensive rats (SHR): negative control (2% tragacanth mucilage), positive control group (perindopril, 0.36 mg/kg/day) and two treatment groups (green tea, 25 mg/kg/day; and combined green tea/perindopril). The treatments were given orally for 14 days. Systolic blood pressure was measured before and after treatment using the tail cuff technique. Angiotensin converting enzyme activity in the lung homogenate of the hypertensive rats was determined spectrophotometrically. Results: Green tea extract significantly reduced the rats' systolic blood pressure (p < 0.05) but did not inhibit the angiotensin-converting enzyme. The combination of green tea extract with perindopril also caused a significant decline in blood pressure (p < 0.001). However, the green tea extract attenuated the inhibition of the angiotensin-converting enzyme activity by perindopril. Conclusion: Green tea extract produces anti-hypertensive activity in rats, but its mechanism of action is not via inhibition of angiotensin-converting enzyme. The interaction of GT extract with perindopril results in a reduction of ACE inhibitory activity. [ABSTRACT FROM AUTHOR]

The progression of atherosclerosis is currently believed to involve the interaction of monocytes with the vascular endothelium. This process is predominantly mediated by cellular adhesion molecules, which are expressed on the vascular endothelium and on circulating leukocytes in response to several inflammatory stimuli. Christia vespertilionis (CV) is herbaceous plants that traditionally used for treatment of various inflammation-related ailments. However, there is limited evidence that points to the protective activity of CV against atherosclerosis. This study aimed to investigate the effect and potential mechanism of CV leaves extract on TNF-a- induced adhesion of macrophage to endothelial cells.3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to determine the effect of GP extract on the cell viability of human vein endothelial cells (HUVECs). Monocyte-endothelial adhesion assay was carried out to determine the effect of GP extract on monocyte adhesion. Western blotting was used to determine protein expression of vascular cell adhesion molecule-1 (VCAM-1).Cell viability was maintained at 80% following 24 hours treatment with CV extract at concentration ranging from 5 µg/mL to 60 µg/mL. CV extract (20, 40 and 60 µg/mL) showed significant inhibitory effect on TNF-a-induced monocyte adhesion in HUVECs (p<0.05). All selected treatment concentrations of CV extract (20, 40 and 60 µg/mL) also significantly inhibited (p<0.05) protein expression of VCAM-1. Protein expression of ICAM-1 was significantly inhibited (p<0.05) by 40 and 60 µg/mL CV extract. Results from this study demonstrated CV extract possessed inhibitory effect of on monocyte adhesion to endothelial cells by inhibiting protein expression of VCAM-1 and ICAM-1. This result implicate that CV potentially have beneficial use particularly in vascular inflammation. [ABSTRACT FROM AUTHOR]

Introduction: Annona muricata L. has gained massive interest from researchers due to its diverse pharmacological aspects, mainly the remarkable anti-inflammatory and anticancer properties. Numerous parts of A. muricata have been extensively used by traditional practitioners in treating various diseases including cancer, inflammation, and diabetes. However, the impact of A. muricata on the immune system has not been extensively studied. Methods: Therefore, the present study was carried out to investigate the immunosuppressive effects of 80% ethanol extract of leaves of A. muricata at 100, 200, and 400 mg/kg on the innate immune responses in male Wistar rats (n=6 for each group). LC-MS/MS was performed to profile the secondary metabolites present in A. muricata. Results: The sub-chronic toxicity study indicated that A. muricata leaf extract did not possess any toxic effect on the vital organs of treated animals. A. muricata demonstrated strong immunosuppressive effects on the innate immune parameters by significantly inhibiting the migration of neutrophils, expressions of Mac-1, phagocytic activity, production of reactive oxygen species, and the expressions of lysozyme and ceruloplasmin in the rat plasma in a dose-dependent manner. Conclusion: A. muricata leaves extract revealed remarkable inhibitory effects on the innate immune responses. Thus, A. muricata has potential to be developed as an agent for the treatment of immune-related disorders. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the inhibitory effects of a chalcone derivative on lipopolysaccharide (LPS)- induced interleukin (IL)-6 and IL-8 secretions and on LPS-induced mitogen-activated protein kinases (MAPK) and nuclear factor kappa B (NF-κB) activation in human U937 macrophage-like cell line. Methods: The effects of chalcone derivative on LPS-induced secretion of IL-6 and IL-8 in endothelial cells were determined by enzyme-linked immunosorbent assay while the effects of chalcone on the activation of MAPK and NF-kB pathway were determined by Western blotting. Results: The results showed that 3-(5-methyl-furan-2-yl)-naphthalen-1-yl-propenone (compound 1) significantly inhibited the secretion of LPS-induced IL-6 and IL-8 in U937 macrophages. This compound also demonstrated significant suppression of c-Jun N-terminal kinases (JNK) and extracellular signalregulated kinases (ERK) phosphorylation. However, the compound did not reverse the degradation of inhibitor kappa B alpha (IκBα) and did not inhibit the phosphorylation of NF-κB subunit and P-38 MAPK. Conclusion: Compound 1 inhibits the secretion of cytokines via the inhibition of ERK and JNK pathways. These results suggest that chalcone derivative could act as an antiinflammatory agent by altering cytokine secretion and inflammatory pathways. [ABSTRACT FROM AUTHOR]

The immune system is the defense mechanism in living organisms that protects against the invasion of foreign materials, microorganisms, and pathogens. It involves multiple organs and tissues in human body, such as lymph nodes, spleen, and mucosa-associated lymphoid tissues. However, the execution of immune activities depends on a number of specific cell types, such as B cells, T cells, macrophages, and granulocytes, which provide various immune responses against pathogens. In addition to normal physiological functions, abnormal proliferation, migration, and differentiation of these cells (in response to various chemical stimuli produced by invading pathogens) have been associated with several pathological disorders. The unwanted conditions related to these cells have made them prominent targets in the development of new therapeutic interventions against various pathological implications, such as atherosclerosis and autoimmune diseases. Chalcone derivatives exhibit a broad spectrum of pharmacological activities, such as immunomodulation, as well as anti-inflammatory, anticancer, antiviral, and antimicrobial properties. Many studies have been conducted to determine their inhibitory or stimulatory activities in immune cells, and the findings are of significance to provide a new direction for subsequent research. This review highlights the effects of chalcone derivatives in different types of immune cells.