A Lanosteryl Triterpene (RA-3) Exhibits Antihyperuricemic and Nephroprotective Effects in Rats.

Considering the global health threat posed by kidney disease burden, a search for new nephroprotective drugs from our local flora could prove a powerful strategy to respond to this health threat. In this study we investigated the antihyperuricemic and nephroprotective potential of RA-3, a plant-derived lanosteryl triterpene. The antihyperuricemic and nephroprotective effect of RA-3 was investigated using the adenine and gentamicin induced hyperuricemic and nephrotoxicity rat model. Following the induction of hyperuricemia and nephrotoxicity, the experimental model rats (Sprague Dawley) were orally administered with RA-3 at 50 and 100 mg/kg body weight, respectively, daily for 14 days. Treatment of the experimental rats with RA-3, especially at 100 mg/kg, effectively lowered the serum renal dysfunction (blood urea nitrogen and creatinine) and hyperuricemic (uric acid and xanthine oxidase) biomarkers. These were accompanied by increased antioxidant status with decrease in malondialdehyde content. A much improved histomorphological structure of the kidney tissues was also observed in the triterpene treated groups when compared to the model control group. It is evident that RA-3 possesses the antihyperuricemic and nephroprotective properties, which could be vital for prevention and amelioration of kidney disease.

Molecular basis of the anti-hyperglycemic activity of RA-3 in hyperlipidemic and streptozotocin-induced type 2 diabetes in rats.

BACKGROUND: Insulin resistance is a hallmark of type 2 diabetes mellitus (T2DM) and the underlying cause of various metabolic changes observed in type 2 diabetic patients. This study investigated the molecular basis of the anti-hyperglycemic activity of the lanosteryl triterpene (RA-3), from Protorhus longifolia stem bark, in hyperlipidemic and streptozotocin (STZ)-induced T2DM in rats. METHODS: The high-fat diet fed (HFD) and STZ-induced T2DM in rat model was used to evaluate the anti-hyperglycemic activity of RA-3. The hyperlipidemic rats received a single intraperitoneal injection of STZ (35 mg/kg body weight) to induce T2DM. The experimental animals received a daily oral single dose of RA-3 (100 mg/kg body) for a period of 28 days, whiles the control group received distilled water only. The animals were euthanized, and skeletal muscle was collected for protein (IRS-1, AKT, GSK and GLUT 4) expression analysis. Western blot confirmed expression of the proteins. RESULTS: Treatment of the diabetic animals with the RA-3 showed marked reduction in fasting plasma glucose levels in comparison to the untreated diabetic group animals. A significant decrease in p-GSK-3ß and p-AKT expression was observed, whereas the expression of IRS-1ser307 were increased when compared to the diabetic control group. This effect was ablated upon treatment with RA-3 and this was concomitant to an observed increase in GLUT 4 expression. CONCLUSIONS: The results obtained in the present study strongly suggested that the anti-hyperglycemic effect of RA-3 could partly be associated with its ability to improve cellular glucose uptake in muscle tissue from T2DM.

Correction to: A Lanosteryl triterpene from Protorhus longifolia augments insulin signaling in type 1 diabetic rats.

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A Lanosteryl triterpene from Protorhus longifolia augments insulin signaling in type 1 diabetic rats.

BACKGROUND: A substantial literature supports antidiabetic properties of the lanosteryl triterpene (methyl-3ß-hydroxylanosta-9,24-dien-21-oate, RA-3) isolated from Protorhus longifolia stem bark. However, the molecular mechanism(s) associated with the antihyperglycemic properties of the triterpene remained to be explored. The current study aimed at investigating the molecular mechanism(s) through which RA-3 improves insulin signaling in streptozotocin-induced type 1 diabetic rats. METHODS: The type 1 diabetic rats were treated daily with a single oral dose of RA-3 (100 mg/kg) for 28 days. The rats were then sacrificed, and blood, skeletal muscle and pancreases were collected for biochemical, protein expression and histological analysis, respectively. RESULTS: Persistently high blood glucose levels in the diabetic control rats significantly increased expression of IRS-1Ser307 while the expression of p-Akt Ser473, p-GSK-3ß Ser9, GLUT 4 and GLUT 2 were decreased. However, enhanced muscle insulin sensitivity, which was indicated by a decrease in the expression of IRS-1ser307 with a concomitant increase in the p-AktSer473, p-GSK-3ß Ser9, GLUT 4 and GLUT 2 expression were observed in the diabetic rats treated with RA-3. The triterpene-treated animals also showed an improved pancreatic ß-cells morphology, along with increased C-peptide levels. An increase in the levels of serum antioxidants such as catalase, superoxide dismutase, and reduced glutathione was noted in the rats treated with the triterpene, while their serum levels of interleukin-6 and malondialdehyde were reduced. CONCLUSIONS: It is apparent that RA-3 is able to improve the insulin signaling in type 1 diabetic rats. Its beta (ß)-cells protecting mechanism could be attributed to its ability to alleviate inflammation and oxidative stress in the cells.

Comparative analyses and structural insights of the novel cytochrome P450 fusion protein family CYP5619 in Oomycetes.

Phylogenetic and structural analysis of P450 proteins fused to peroxidase/dioxygenase has not been reported yet. We present phylogenetic and in silico structural analysis of the novel P450 fusion family CYP5619 from the deadliest fish pathogenic oomycete, Saprolegnia diclina. Data-mining and annotation of CYP5619 members revealed their unique presence in oomycetes. CYP5619 members have the highest number of conserved amino acids among eukaryotic P450s. The highest number of conserved amino acids (78%) occurred in the peroxidase/dioxygenase domain compared to the P450 domain (22%). In silico structural analysis using a high-quality CYP5619A1 model revealed that CYP5619A1 has characteristic P450 structural motifs including EXXR and CXG. However, the heme-binding domain (CXG) in CYP5619 members was found to be highly degenerated. The in silico substrate binding pattern revealed that CYP5619A1 have a high affinity to medium chain fatty acids. Interestingly, the controlling agent of S. diclina malachite green was predicted to have the highest binding affinity, along with linoleic acid. However, unlike fatty acids, none of the active site amino acids formed hydrogen bonds with malachite green. The study's results will pave the way for assessing CYP5619A1's role in S. diclina physiology, including the nature of malachite green binding.

Testicular Dysfunction Ameliorative Effect of the Methanolic Roots Extracts of Maytenus procumbens and Ozoroa paniculosa.

The traditional use of medicinal plants in the management of sexual dysfunctions has a long history. This study investigated testicular dysfunction ameliorative effect of the methanolic roots extracts of Maytenus procumbens and Ozoroa paniculosa in a butanol-induced testicular dysfunction rat model. The rats in respective experimental groups were orally administered with the extract at 50 and 250 mg/kg bw, daily for 28 days. The cytotoxicity of the extracts was evaluated against HEK293, MCF-7, and HT29 cell lines. The extracts exhibited moderate (LC50 30.3-330.2 µg/mL) to weak (LC50 200.8-438.4 µg/mL) cytotoxicity level on the cancer and normal cells, respectively. While relatively lower serum testosterone levels and total sperm count along with decreased numbers of spermatogonia were noted in the untreated group, all these parameters were improved in the groups treated with the extracts at 250 mg/kg. Improved histomorphological changes of the testes were also observed when compared to the untreated group. While the extracts (at 250 mg/kg) increased serum reduced glutathione content and decreased malondialdehyde content, a relatively higher serum creatinine level was also observed in the treated animals group. The results indicate that the two plant extracts have potential to ameliorate testicular dysfunction.