Eugenia sonderiana O. Berg leaves: Phytochemical characterization, evaluation of in vitro and in vivo antidiabetic effects, and structure-activity correlation.

Several medicinal plants have drawn the attention of researchers by its phytochemical composition regarding their potential for treating chronic complications of diabetes mellitus. In this context, plants of the Myrtaceae family popularly used in Brazil for the treatment of diabetes mellitus, including Eugenia sonderiana, have shown beneficial effects due to the presence of phenolic compounds and saponins in their chemical constitution. Thus, the present work aimed to perform the phytochemical characterization of the hydroethanolic extract of E. sonderiana leaves using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS), along with in vitro and in vivo studies of antidiabetic activity. The chemical characterization revealed the presence of phenolic compounds, flavonoids, neolignans, tannins, and saponins. In addition, the extract exhibited minimum inhibitory concentrations of alpha-amylase and alpha-glycosidase higher than the acarbose in the in vitro tests. Also, the in vivo tests revealed a slight increase in body mass in diabetic rats, as well as a significant decrease in water and feed consumption provided by the extract. Regarding serum biochemical parameters, the extract showed significant activity in decreasing the levels of glucose, hepatic enzymes, and triglycerides, in addition to maintaining HDL cholesterol levels within normal ranges, protecting the cell membranes against oxidative damage. Thus, the extract of E. sonderiana leaves was considered promising pharmaceutical ingredient in the production of a phytotherapy medication.

Apigetrin-enriched Pulmeria alba extract prevents assault of STZ on pancreatic ß-cells and neuronal oxidative stress with concomitant attenuation of tissue damage and suppression of inflammation in the brain of diabetic rats.

In the present study, in vitro, in vivo, and in silico models were used to evaluate the therapeutic potential of Pulmeria alba methanolic (PAm) extract, and we identified the major phytocompound, apigetrin. Our in vitro studies revealed dose-dependent increased glucose uptake and inhibition of α-amylase (50% inhibitory concentration (IC50)= 217.19 µg/mL), antioxidant (DPPH, ferric-reducing activity of plasma (FRAP), and lipid peroxidation (LPO) [IC50 = 103.23, 58.72, and 114.16 µg/mL respectively]), and anti-inflammatory potential (stabilizes human red blood cell (HRBC) membranes, and inhibits proteinase and protein denaturation [IC50 = 143.73, 131.63, and 198.57 µg/mL]) by the PAm extract. In an in vivo model, PAm treatment reversed hyperglycemia and attenuated insulin deficiency in rats with streptozotocin (STZ)-induced diabetes. A post-treatment tissue analysis revealed that PAm attenuated neuronal oxidative stress, neuronal inflammation, and neuro-cognitive deficiencies. This was evidenced by increased levels of antioxidants enzymes (superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH)), and decreased malondialdehyde (MDA), proinflammatory markers (cyclooxygenase 2 (COX2), nuclear factor (NF)-κB and nitric oxide (NOx)), and acetylcholinesterase (AChE) activities in the brain of PAm-treated rats compared to the STZ-induced diabetic controls. However, no treatment-related changes were observed in levels of neurotransmitters, including serotonin and dopamine. Furthermore, STZ-induced dyslipidemia and alterations in serum biochemical markers of hepatorenal dysfunction were also reversed by PAm treatment. Extract characterization identified apigetrin (retention time: 21,227 s, 30.48%, m/z: 433.15) as the major bioactive compound in the PAm extract. Consequently, we provide in silico insights into the potential of apigetrin to target AChE/COX-2/NOX/NF-κB Altogether the present study provides preclinical evidence of the therapeutic potential of the apigetrin-enriched PAm extract for treating oxidative stress and neuro-inflammation associated with diabetes.

Effects of Phoenix dactylifera against Streptozotocin-Aluminium Chloride Induced Alzheimer's Rats and Their In Silico Study.

Phoenix dactylifera is known for medicinal importance due to its antioxidant, antidiabetic, antidepressant, and anti-inflammatory properties. This study is aimed at evaluating the effect of P. dactylifera seeds to cure Alzheimer's disease (AD). AD was induced in the rats with streptozotocin + aluminium chloride followed by treatment of methanolic extract of P. dactylifera seeds. The blood glucose levels were determined at regular intervals, which showed a prominent decrease in the extracts treated group. Behavior tests, including the Elevated Plus Maze (EPM) test and Morris Water Maze (MWM) test, were used to evaluate memory patterns in rats. The results indicated that extract-treated rats significantly improved memory behavior compared to the diseased group. After dissection, the serum electrolytes, antioxidant enzymes, and choline esterase enzymes were measured in different organs. The serum parameters creatinine, urea, and bilirubin increased after extract treatment. Similarly, the level of antioxidant enzymes like peroxidases (POD), glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), and thiobarbituric acid reactive substance (TBARS) in the extract-treated group showed improved results that were close to the normal control group. The enzyme (lipase, insulin, amylase, and acetylcholine) levels were found enhanced in extract groups as compared to diseased rats. High-performance liquid chromatography (HPLC) was used to determine the level of dopamine and serotonin neurotransmitters, which were increased significantly for P. dactylifera seeds with values of 0.18 µg/mg tissue and 0.56 µg/mg tissue, respectively. Overall, results showed that P. dactylifera seeds proved to be quite efficient in improving the memory and behavior of treated rats. The antioxidants and enzymes were also increased; therefore, it may be a potential candidate for treating AD.