Ameliorating effect of Malva Neglecta on hyperglycemia and hyperlipidemia in diabetic rats

Ginsenoside Rg1 Improves Inflammation and Autophagy of the Pancreas and Spleen in Streptozotocin-Induced Type 1 Diabetic Mice

BACKGROUND

Ginsenoside Rg1 (Rg1) is one of the key bioactive components of the precious Traditional Chinese Medicine that has been used to treat diabetes in China. Ginsenosides have been reported to protect diabetics from tissue damage, inflammation, and insulin resistance. Type 1 diabetes (T1D) is an organ-specific autoimmune disease that occurred frequently among adolescents over the world, its development was related to inflammation and β-cells immunodeficiency. The aim of this study is to explore the biological mechanism of Rg1 on inflammation and autophagy of β-cells in T1D and its therapeutic potential.

METHODS

The model of T1D mice was established by injecting Streptozotocin (STZ) (55 mg/kg) or citric acids once a day for 5 days and from the fourth day of injection, mice were administered with Rg1 (20 mg/kg) or saline by gavage once a day for 12 days. Hematoxylin-eosin staining, immunofluorescence, ELISA, quantitative real-time PCR, and Western blot were used to observe the histopathological changes, inflammatory factor levels, and autophagy markers after administration of ginsenoside Rg1.

RESULTS

Compared to the T1D mice, Rg1 improved the weight (p < 0.05) and blood glucose (p < 0.01) of mice, advanced the injury and apoptosis of β-cells in islets (p < 0.01), and markedly inhibited the protein expression degrees of CD45, CXCL16, ox-LDL, and TF in the pancreas and spleens (p < 0.01), also activated the degrees of insulin in serum (p < 0.01). Besides, in T1D mice' pancreas and spleen, Rg1 markedly repressed the IL-1β, TNF-α, and NOS2 mRNA levels (p < 0.05 or p < 0.01), inhibited the CXCL16, NF-κB, and TF proteins (p < 0.05 or p < 0.01), while elevating the ratio of LC3 II/I (p < 0.01) and P62 (p < 0.05) protein level.

CONCLUSIONS

This study proved that Rg1 protected mice against T1D possibly by improving islet injury and tissue inflammation, raising serum insulin, and tissue autophagy marker.

Ameliorating Effect of Malva neglecta Wallr on Obesity and Diabetes in Wistar Rats: A Mechanistic Study

A high caloric food causes deposition of fats that may progress to obesity. Obesity is a risk factor for various metabolic and cardiovascular diseases, including but limited to diabetes mellitus. This study is aimed at determining the ameliorating effect of Malva Neglecta wallr aqueous-methanolic extract (MNME) on obesity and diabetes in Wistar rats. The MNME was chemically characterized by high-performance liquid chromatography (HPLC). The plant extract was evaluated by in vitro α-amylase inhibition and DPPH scavenging activities. Obesity was induced by administering high sugar and fat diet (HSFD) to rats for six weeks, followed by intraperitoneal injection of alloxan monohydrate (150 mg/kg) to induce diabetes. Oral treatments with MNME 250, 500, and 750 mg/kg/day were given to diabetic obese rats for 14 days. The HPLC analysis showed the presence of phenolic acids and flavonoids. The plant extract showed significant antioxidant (P < 0.001) and alpha-amylase (P < 0.0001) inhibition activities. The administration of MNME displayed a considerable decrease in fasting blood glucose, body weight, liver function tests, urea, cholesterol, leptin, and insulin levels in diabetic obese rats as compared to the disease control group and maximum effect were observed at 750 mg/kg/day of MNME. The MNME significantly increased (P < 0.05 − 0.001) the levels of GSH, SOD, and CAT in the liver, kidney, and pancreas while notably (P < 0.05 − 0.001) reduced the malondialdehyde level in kidney and pancreas of diabetic obese rats in contrast to disease control rats. This experimental study concludes that the MNME had exhibited antiobesity and antidiabetic activities through reduction of oxidative stress, leptin, α-amylase activity, and insulin resistance due to the presence of phenolic acid and flavonoid compounds.