Novel Niacin Receptor Agonists: A Promising Strategy for the Treatment of Dyslipidemia.

Author(s):  
Prajakta B. Kothawade ◽  
Asha B. Thomas ◽  
Sohan S. Chitlange

Background: Hyperlipidemia is characterized by high level of cholesterol and triglycerides in blood. Various classes of drugs like statins, fibrates, niacin etc. are used for treatment of hyperlipidaemia. Objective: Niacin, which is one of the beneficial anti-hyperlipidemic agents, helps to lower LDL cholesterol by 20 to 40% and causes increase of HDL cholesterol by 20 to 35%. However cutaneous flushing, loss of glucose tolerance, liver toxicity are the reported side effects of niacin therapy responsible for decreased patient compliance. Very recently, the G protein coupled receptor (GPCR); GPR109A located on the adipocytes has been identified as the receptor for activation of niacin. Method: In-vitro studies have demonstrated that GPR109A receptor having high affinity for niacin. The present review attempts to provide a systematic presentation of the various chemical classes of compounds that have been reported as novel niacin receptor agonists including pyrazole-3-carboxylic acids, urea derivatives, anthranilic acids, biaryl anthranilides, tetrahydro anthranilic acid, xanthines, barbituric acid, bicyclic pyrazole carboxylic acids, pyrido pyrimidinones, pyrazolyl propionyl cyclohexenamides, pyrazole acids etc. Results : As the design of GPR109A receptor agonists offers a promising solution for treatment of dyslipidemia, this review will be beneficial for medicinal and drug discovery chemists to expediate the process of discovery of new class of antihyperlipidemic agent with favorable lipid lowering profile with increase in HDL levels. Conclusion: This review explains about novel GPR109A receptor agonist for the treatment of dyslipidemia.

2019 ◽  
Vol 19 (2) ◽  
pp. 189-198 ◽  
Author(s):  
Mohammed Ajebli ◽  
Fadwa El Ouady ◽  
Mohamed Eddouks

Background and Objective: Warionia saharae Benth & Coss, a plant belonging to Asteraceae family, is used for its anti-diabetic properties in Morocco. The objective of this study was to evaluate the effect of tannins extracted from Warionia saharae (W. saharae) on blood glucose levels and lipid profile in normal and streptozotocin(STZ)-induced diabetic rats. Methods: Tannins (TE) were extracted from W. saharae using Soxhlet apparatus and different organic solvents. Single and once daily repeated oral administration of TE (10 mg/kg) for 15 days were used to evaluate the glucose and lipid-lowering activity in normal and diabetic rats. Furthermore, glucose test tolerance, liver histopathological examination and in vitro antioxidant activity of TE were carried out in this study. Results: The results showed that TE was able to exert antihyperglycemic and lowering total cholesterol effects as well as improvement of the high-density lipoprotein (HDL)-cholesterol serum level after 15 days of treatment. Furthermore, TE improved glucose tolerance, histopathological status of liver in diabetic rats and demonstrated interesting antioxidant activity. Conclusion: In conclusion, the present investigation revealed that TE possesses potent antidiabetic and antihyperlipidemic activities as claimed in different ethnopharmacological practices.


Author(s):  
Sukumar Danadapat ◽  
Manoj Kumar ◽  
Rakesh Ranjan ◽  
Manoranjan Prasad Sinha

Pleurotus tuber-regium has been used as fodder and traditionally used as medicinal supplement. The aim of this study was to screen in vitro proximate biochemical composition and nutritional potentiality of P. tuber-regium extract for further in vivo analysis of impact of the extract on serum lipid and testosterone profile of rats. Total cholesterol, HDL cholesterol, LDL cholesterol were measured photometrically. Testosterone was measured by chemiluminescence immune assay. P. tuber-regium extract contains different biochemicals such as proteins, carbohydrates, tannins, flavonoids, phenols etc. and showed highly quantified calorific value (297.89±1.92 calori/100g). Acute toxicity test showed no mortality and toxic behavioural symptoms. Significant decrease in total cholesterol (75.52±0.39mg/dL), LDL cholesterol (34.58±1.69mg/dL) and triglyceride (81.31±1.25) were observed in rat group treated with 200mg/kg dose of extract. 400mg/kg dose of extract showed higher efficacy than 200mg/kg dose of extract and significantly decreased total cholesterol (72.25±1.11mg/dL), LDL cholesterol (26.37±1.21mg/dL) and triglyceride (69.42±0.72). The extract showed testosterone enhance efficacy. 400mg/kg dose of extract showed high level testosterone (178.96±0.68 ng/dL) enhance efficacy than 200mg/kg dose (174.64±0.64ng/dL). Due to hypocholesterolaemia and testosterone elevating properties of P. tuber-regium extract, it can be said that, mushroom P. tuber-regium can be consumed as healthy diet supplement to maintain cholesterol level and to maintain good male reproductive health.


VASA ◽  
2005 ◽  
Vol 34 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Brunner-La Rocca ◽  
Schindler ◽  
Schlumpf ◽  
Saller ◽  
Suter

Background: Previous studies showed an anti-atherosclerotic effect of PADMA 28, an herbal formula based on Tibetan medicine. As the mechanisms of action are not fully understood, we investigated whether PADMA 28 may lower blood lipids and lipid oxidisability, and affect early endothelial dysfunction. Patients and methods: Sixty otherwise healthy subjects with total cholesterol ≥5.2 mmol/l and < 8.0 mmol/l were randomly assigned to placebo or PADMA 28, 3 x 2 capsules daily, for 4 weeks (double-blind). Blood lipids (total, LDL-, and HDL-cholesterol, triglycerides, Apo-lipoprotein A1 and B) and ex vivo lipid oxidisability were measured before and after treatment. In a subset of 24 subjects, endothelial function was assessed using venous occlusion plethysmography with intraarterial infusion of acetylcholine. Isolated LDL and plasma both untreated and pre-treated with PADMA 28 extract were oxidised by the radical generator AAPH. Conjugated diene formation was measured at 245 nm. Results: Blood lipids did not change during the study in both groups. In contrast to previous reports in mild hypercholesterolaemia, no endothelial dysfunction was seen and, consequently, was not influenced by therapy. Ex vivo blood lipid oxidisability was significantly reduced with PADMA 28 (area under curve: 5.29 ± 1.62 to 4.99 ± 1.46, p = 0.01), and remained unchanged in the placebo group (5.33 ± 1.88 to 5.18 ± 1.78, p > 0.1). This effect persisted one week after cessation of medication. In vitro experiments confirmed the prevention of lipid peroxidation in the presence of PADMA 28 extracts. Persistent protection was also seen for LDL isolated from PADMA 28-pretreated blood after being subjected to rigorous purification. Conclusions: This study suggests that the inhibition of blood lipid oxidisability by PADMA 28 may play a role in its anti-atherosclerotic effect.


2019 ◽  
Vol 15 (4) ◽  
pp. 415-426
Author(s):  
Avani B. Chokshi ◽  
Mahesh T. Chhabria ◽  
Pritesh R. Desai

Background:Squalene Synthase is one of the cholesterol biosynthetic pathway enzymes, inhibition of which produces potent lipid lowering action. A variety of chemical classes have been evaluated for its inhibition to provide alternate antihyperlipidemic agents to statins.Methods:A series of N-substituted-sulfomoyl-phenyl-amino carboxylic acid derivatives were designed through pharmacophore modelling as Squalene Synthase inhibitors. We report here the synthesis, characterization and in vitro pharmacological screening of the designed molecules as Squalene synthase inhibitors. The target molecules were synthesized by a simple procedure and each molecule was characterized by IR, Mass, 1HNMR and 13CNMR spectroscopic techniques. As a primary site of action for cholesterol biosynthesis is liver, each of the molecules were first screened for in vitro cytotoxicity over human hepatic cell line (HepG2) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay method. The enzyme inhibition assay was performed on cell lysates prepared from HepG2 cells by Human Squalene Synthase ELISA kit, where test compounds were added in the nontoxic concentrations only.Results:Compound 5f was found to be most potent with the IC50 value of 11.91 µM. The CTC50 value for 5f on human hepatic cell line was > 1000 µM so it was considered that the compound was relatively safe and might be free of hepatotoxicity.Conclusion:From the results of our studies, it was observed that compounds with poly nuclear aromatic or hetero aromatic substituent on a side chain were more potent enzyme inhibitors and a distance of 4-5 atoms is optimum between amide nitrogen and hydroxyl group of carboxylic acid.


Author(s):  
Anchal Trivedi ◽  
Aparna Misra ◽  
Esha Sarkar ◽  
Anil K. Balapure

Background: In recent years, great progress has been made in reducing the high level of malaria suffering worldwide. There is a great need to evaluate drug resistance reversers and consider new medicines against malaria. There are many approaches to the development of antimalarial drugs. Specific concerns must be taken in to account in these approaches, in particular there requirement for very in expensive and simple use of new therapies and the need to limit drug discovery expenses. Important ongoing efforts are the optimisation of treatment with available medications, including the use of combination therapy. The production of analogs of known agents and the identification of natural products, the use of compounds originally developed against other diseases, the assessment of overcoming drug resistance and the consideration of new therapeutic targets. Liver and spleen are the important organs which are directly associated with malarial complications. Aim: An analysis the Activity of Adenosine Triphosphatase, Aryl Hyrocarbon Hydroxylase Enzymes and Malondialdehyde in spleen Explant Culture. Objective: To determine in-Vitro Effect of Chlorquine and Picroliv on Plasmodium Berghei Induced Alterations in the Activity of Adenosine Triphosphatase, Aryl Hyrocarbon Hydroxylase Enzymes and Malondialdehyde in spleen Explant Culture. Material and method: 1-Histological preparation of spleen explants for paraplast embedding 2-Biochemicalstudies (Enzymes (Atpase, ALP&GST) and the level of protein, Malondialdehyde (MDA). Result: Splenomegalyis one of the three main diagnostic parameters of malaria infection besides fever and anaemia. Many enzymes present in the liver and spleen may also be altered or liberated under different pathological conditions. Enzymes (ATPase, ALP&GST) and the level of protein, Malondialdehyde (MDA) content was found to increase in the liver and spleen explants during malarial infection. In the liver and spleen derived from parasitized CQ treated animals, the activity of all the above enzymes (ATPase, ALP&GST) and the level of protein & MDA of liver/spleen reversed towards the normal for all the 4or3 days of incubations. Picroliv efficacy decreased with the increment of parasitaemia and at 60%parasitaemia. Conclusion: Alkalinephosphatase (ALP) was found to increase with increasing parasitaemia. After the addition of Picroliv to the medium, a decrement in the activity was observed up to day 4 of culture.A similar positive effect of Picroliv was observed on the ATPase and ALP activity of spleen explants.DNA and protein contents also increased in the parasitized liver cultured in the presence of picroliv.On the contrary, in the spleen explants DNA, protein and MDA content were found to decrease after Picroliv supplementation to the culture medium.


Author(s):  
Fadwa El-ouady ◽  
Fatima Bachir ◽  
Mohamed Eddouks

Aim: This study aimed to evaluate the antidiabetic and antihyperlipidemic effects of Asteriscus graveolens. Background: Asteriscus graveolens (Asteraceae) is a medicinal plant widely used by the Moroccan population to treat various diseases including diabetes. Objective: This work aimed to assess the capacity of flavonoids extracted from Asteriscus graveolens (FEE) to improve diabetes mellitus and dyslipidemia in normal and STZ-induced diabetic rats. Methods: Flavonoids were extracted from A. graveolens using the Soxhlet apparatus and using different organic solvents. Normal and streptozotocin-induced diabetic rats were treated orally by the extract of A. graveolens at a dose of 10 mg/kg. The oral treatment during 15 days was used to evaluate the effect of the flavonoids extracted from A. graveolens on blood glucose level and lipid profile in normal and diabetic rats. The oral glucose tolerance test as well as the analysis of histopathological examination of liver was performed. The antioxidant activity of FEE was also assessed by the method of trapping of free radical 2,2-diphenyl-1 picrylhydrazyl (DPPH), in order to estimate the mechanisms of action involved by FEE to improve hyperglycemia and lipid profile in normal and diabetic rats. Results: FEE reduced serum glucose concentrations in both normal and diabetic rats and exhibited in the last group lowering total cholesterol and triglycerides effects as well as improvement of the HDL-cholesterol serum level. In addition, a remarkable influence on glucose tolerance was also noticed after FEE treatment. Moreover, FEE was able to improve histopathological status of liver and possess a potential antioxidant effect in vitro. Conclusion: In conclusion, this study demonstrates the hypoglycemic and antihyperlipidemic effects of FEE in rats supporting then its traditional use for the management of diabetes.


2020 ◽  
Vol 6 (2) ◽  
pp. 155-169
Author(s):  
Neeraj Panihar ◽  
Neeru Vasudeva ◽  
Sunil Sharma ◽  
Babu Lal Jangir

Background: Fagopyrum esculentum Moench. is a herb consumed as food and has medicinal value. It is a rich source of bioactive nutrients which cure and prevent many ailments. Traditionally, it is used to treat hypertension, diabetes, constipation, cancer etc. Methods and Objective: Present work illustrates morphological, microscopic and physicochemical parameters of Fagopyrum esculentum seeds as per WHO guidelines, in vitro antioxidant activity; assessed by DPPH scavenging method, hydrogen peroxide scavenging assay and β-carotene linoleic acid bleaching method and study of lipid lowering potential of the ethyl acetate and ethanol extract of seeds on normal diet fed Wistar rats. Results: Morphological studies delineated the triangular shape, dark brown colour, 8 mm length and 6 mm width of the seed. The microscopic examination of the transverse section of seed depicted features like testa or pericarp (seed coat), the endosperm, embryo and sclerenchyma cells. Study of physiochemical parameters exhibited 0.3±0.02% of foreign matter and 1.44±0.51% crude fibre content. Total ash, acid insoluble ash and water soluble ash value were 6.7±1.7%, 1.9±0.23% and 3.9± 0.31% respectively. Alcohol soluble and water soluble extractive value came out to be 65.02± 3.21 mg/g and 12.7±1.24 mg/g respectively. Foaming index was less than 100, swelling index was found to be 0.5±0.01 ml/g. Loss on drying was 4.02±1.27%. Phytochemical screening of ethyl acetate and ethanol extract revealed the presence of alkaloids, carbohydrates, phenolic compounds, phytosterols and flavonoids. Trace amount of heavy metals (arsenic, cadmium, lead, mercury) were determined by atomic absorption spectrophotometer. Pesticide residue analysis confirmed the presence of nontoxic pesticides like dimethipin, hymexazol, phenothrin-2, methoprene, triadimenol, prohydrojasmon- 1, jasmolin ii, triademinol, jasmolin i, prohydrojasmone i, cyromazine in both the extracts by gc-ms spectrometer. The ethyl acetate and ethanol extract has shown significant in-vitro antioxidant activities demonstrated by the DPPH method (IC50 = 94.37±2.51 and 216.04±4.39 μg/ml respectively), hydrogen peroxide scavenging assay (IC50 = 83.72±3.72 and 193.47±5.05 µg/ml respectively) and β-carotene bleaching method (IC50 = 100.67±4.01 and 205.39±2.89 µg/ml respectively). Lipid lowering study performed on Wistar rats demonstrated a significant (p<0.001) decrease in serum Total Cholesterol (TC), Triglyceride (TG) and increase in High Density Lipoprotein (HDL) level as compared to normal group. Both the extracts have shown a non significant difference in the level of TG as compared to standard drug atorvastatin, depicting that the efficacy of extracts is at par with that of standard drug atorvastatin. Conclusion: Pharmacognostical study of the plant can be a very good tool for identification as well as authentication of a herb. Moreover, these parameters may be helpful in the development of monograph of the plant. Pharmacological activity confirmed Fagopyrum esculentum Moench. seed to be a good antioxidant and have lipid lowering potential.


2020 ◽  
Vol 65 (1) ◽  
pp. e01948-20
Author(s):  
Dalin Rifat ◽  
Si-Yang Li ◽  
Thomas Ioerger ◽  
Keshav Shah ◽  
Jean-Philippe Lanoix ◽  
...  

ABSTRACTThe nitroimidazole prodrugs delamanid and pretomanid comprise one of only two new antimicrobial classes approved to treat tuberculosis (TB) in 50 years. Prior in vitro studies suggest a relatively low barrier to nitroimidazole resistance in Mycobacterium tuberculosis, but clinical evidence is limited to date. We selected pretomanid-resistant M. tuberculosis mutants in two mouse models of TB using a range of pretomanid doses. The frequency of spontaneous resistance was approximately 10−5 CFU. Whole-genome sequencing of 161 resistant isolates from 47 mice revealed 99 unique mutations, of which 91% occurred in 1 of 5 genes previously associated with nitroimidazole activation and resistance, namely, fbiC (56%), fbiA (15%), ddn (12%), fgd (4%), and fbiB (4%). Nearly all mutations were unique to a single mouse and not previously identified. The remaining 9% of resistant mutants harbored mutations in Rv2983 (fbiD), a gene not previously associated with nitroimidazole resistance but recently shown to be a guanylyltransferase necessary for cofactor F420 synthesis. Most mutants exhibited high-level resistance to pretomanid and delamanid, although Rv2983 and fbiB mutants exhibited high-level pretomanid resistance but relatively small changes in delamanid susceptibility. Complementing an Rv2983 mutant with wild-type Rv2983 restored susceptibility to pretomanid and delamanid. By quantifying intracellular F420 and its precursor Fo in overexpressing and loss-of-function mutants, we provide further evidence that Rv2983 is necessary for F420 biosynthesis. Finally, Rv2983 mutants and other F420H2-deficient mutants displayed hypersusceptibility to some antibiotics and to concentrations of malachite green found in solid media used to isolate and propagate mycobacteria from clinical samples.


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