Shahidul Islam

Whole Leea macrophylla ethanolic extract normalizes kidney deposits and recovers renal impairments in an ethylene glycol–induced urolithiasis model of rats

OBJECTIVE To investigate the antilithiatic effect of the whole Leea macrophylla (L. macrophylla) Roxb (Leeaceae) ethanol extract in ethylene glycol-induced urolithiasis model of rats. METHODS Forty two seven weeks old male wistar albino rats were randomly divided into two major groups namely: preventive (n=18) and therapeutic (n=24). Preventive group was further subdivided into 3 groups of 6 rats namely: preventive control (PC), preventive lithiatic control (PLC) and preventive lithiatic L. macrophylla (PLLM). Similarly, therapeutic group was also subdivided into 4 groups of 6 rats namely: therapeutic control (TC), therapeutic lithiatic control (TLC), therapeutic lithitatic L. macrophylla (TLLM) and therapeutic lithiatic cystone (TLCYS). The lithiasis was induced by 0.75% (v/v) ethylene glycol in the drinking water of all groups except the PC and TC groups. The urinary ionic parameters such as calcium, inorganic phosphate, oxalate, magnesium & creatinine and renal morphology were altered by ethylene glycol, which were partially recovered by 14 d preventive and almost fully recovered by 28 d therapeutic intervention trials with L. macrophylla extract (500 mg/kg BW daily). RESULTS Significant difference on recovery was observed between preventive and therapeutic interventional trials. Anti-urolithiatic effect of cystone was significantly (P<0.001) higher than extracts. L. macrophylla extract was found nontoxic in the acute toxicity test. CONCLUSION The results of this study demonstrated very promising anti-urolithiatic effect of L. macrophylla extract with preventive and therapeutic treatments in this experimental condition.

Phenolics-rich fraction of Khaya senegalensis stem bark: Antitrypanosomal activity and amelioration of some parasite-induced pathological changes

Abstract Context: The stem bark of Khaya senegalensis A. Juss (Meliaceae) is currently used for the treatment of trypanosomiasis by traditional practitioners in Nigeria. Objectives: The present study investigated the anti-Trypanosoma brucei brucei activity of phenolics-rich fraction of K. senegalensis (pfks) and its ameliorative effects on trypanosome-induced pathological changes. Materials and methods: The fraction was initially analyzed by gas chromatography-mass spectrometry (GC-MS). A 60 min time course experiment was conducted with various concentrations of the fraction using a 96-well microtiter plate technique and was further used to treat T. brucei infected rats at 100, 200 and 300 mg/kg body weight (BW). Indices of anemia as well as hepatic and renal functions were analyzed in all experimental animals at the end of the experiment. Results: The GC-MS analysis of the pfks revealed that the most abundant phytochemicals are phloroglucinol (40.56%) and 3,4-(dihydroxyphenyl) acetic acid (41.76%). The fraction showed a concentration dependent in vitro antitrypanosomal activity. Interestingly, the fraction completely eliminated the parasites from the bloodstream of infected rats without relapse during the experimental period at the dose of 300 mg/kg BW and also kept the parasites consistently lower at 100 and 200 mg/kg BW than that was recorded in the untreated infected rats. Furthermore, the severity of T. brucei-induced anemia and hepatic damage was significantly (p < 0.05) ameliorated in the 300 mg/kg BW treatment group whereas the parasite-induced renal damage was significantly (p < 0.05) ameliorated in all treatment groups. Conclusion: Data from this study may suggest that phenolics play an important role in the antitrypanosomal activity of K. senegalensis.

Alpinia calcarata Roscoe: A potential phytopharmacological source of natural medicine

Alpinia calcarata Roscoe (Family: Zingiberaceae), is a rhizomatous perennial herb, which is commonly used in the traditional medicinal systems in Sri Lanka. Alpinia calcarata is cultivated in tropical countries, including Sri Lanka, India, and Malaysia. Experimentally, rhizomes of Alpinia calcarata are shown to possess antibacterial, antifungal, anthelmintic, antinociceptive, anti-inflammatory, antioxidant, aphrodisiac, gastroprotective, and antidiabetic activities. Phytochemical screening revealed the presence of polyphenols, tannins, flavonoids, steroid glycosides and alkaloids in the extract and essential oil of this plant. Essential oil and extracts from this plant have been found to possess wide range of pharmacological and biological activities. This article provides a comprehensive review of its ethnomedical uses, chemical constituents and the pharmacological profile as a medicinal plant. Particular attention has been given to the pharmacological effects of the essential oil of Alpinia calcarata in this review so that the potential use of this plant either in pharmaceutics or as an agricultural resource can be evaluated.

Synthesis, in vitro antimicrobial, antioxidant, and antidiabetic activities of thiazolidine–quinoxaline derivatives with amino acid side chains

A novel protocol for the rapid assembly of a hybrid framework based on amino acid, thiazolidine and quinoxaline scaffolds has been demonstrated by microwave irradiation. The quinoxalines with amino acid side chains 5a–5c were prepared in three steps from 2,4-dinitrofluorobenzene and the amino acids, valine, methionine, and tyrosine and subsequently reacted with four different aldehydes and thioglycolic acid to produce thiazolidine–quinoxaline hybrids with amino acid side chains 6a–6l. All synthesized compounds were evaluated for their in vitro antimicrobial, antioxidant, and antidiabetic activities. Compounds 6f, 6j, and 6k showed broad spectrum antimicrobial activity against Gram +ve and Gram –ve bacteria, whilst 6h, 6k, and 6l showed the best antioxidant activity in the same order of magnitude to that of ascorbic acid. Four of the compounds, 5c, 6d, 6g, and 6k showed activity against α-glucosidase and α-amylase similar to acarbose. Those compounds showing antibacterial activity possessed 4-fluorophenyl and 4-methoxyphenyl groups along with methionine and tyrosine side chains while the compounds showing antioxidant, α-glucosidase, and α-amylase activity contained 4-nitrophenyl and 4-methoxyphenyl groups on the thiazolidine moiety with mainly methionine and tyrosine side chains. The α-glucosidase and α-amylase inhibitory compound 5c did not have a thiazolidine moiety and 6d was the only active compound with a valine amino acid side chain. Compound 6k with a tyrosine side chain and a 4-methoxyphenylthiazolidine moiety on the quinoxaline scaffold showed good bioactivity in all three assays.Graphical Abstract

Boerhaavia diffusa inhibits key enzymes linked to type 2 diabetes in vitro and in silico; and modulates abdominal glucose absorption and muscle glucose uptake ex vivo

The present study investigated the in vitro and ex vivo antioxidant, anti-diabetic and anti-obesogenic potentials of different solvent (ethyl acetate, ethanol and water) extracts from the aerial parts of Boerhaavia diffusa. The ferric reducing antioxidant power (FRAP), DPPH scavenging activity and the ameliorative effects of the extracts on Fe2+-induced oxidative injury was investigated both in vitro and ex vivo. Alpha glucosidase and pancreatic lipase inhibitory potentials of the extracts were examined in vitro, while the effects of the ethanol extract on abdominal glucose intake and muscle glucose uptake were determined in freshly harvested tissues ex vivo. The extracts were subjected to Gas Chromatography-Mass Spectrometry (GC-MS) analysis to identify their possible bioactive components. The ethanol extract showed the most potent FRAP and DPPH radical scavenging activities compared to other extracts. All extracts increased catalase and SOD activities, and GSH levels in oxidative pancreatic injury. Both ethanol and aqueous extracts exhibited remarkable enzyme inhibitory activities, which was significantly higher than ethyl acetate extract and acarbose but was not comparable to orlistat. The ethanol extract portrayed a dose-dependent inhibitory effect on jejunal glucose uptake and enhancement of muscle glucose uptake. 9-(4 methoxyphenyl) xanthene, xanthone and stigmasterol showed strong binding affinities for α-glucosidase and lipase enzymes tested. Data from this study suggest that aerial parts of B. diffusa (particularly the ethanol extract) may not only exhibit antioxidant potentials but may also mediate anti-lipidemic and anti-hyperglycemic effects via inhibiting fat and carbohydrate digestion as well as abdominal glucose intake and enhancing muscle glucose uptake.