METHODS: Forty female rats were randomly assigned into five groups (n = 8/group) i.e. non-DM (non-diabetes), DM (diabetes), DM + Propolis (diabetes on propolis orally); DM + Insulin (diabetes on insulin subcutaneously) and DM + Combined (diabetes on propolis and insulin) groups. Propolis and insulin were given at 300 mg/kg/day orally and 5.0 IU/kg/day subcutaneously, respectively, for 4 weeks.

RESULTS: Fasting blood glucose, conception period, implantation losses, foetal blood glucose and placental oxidative stress markers such as malonaldehyde and protein carbonyl were significantly higher while maternal weight gain, foetal body weight and total antioxidant capacity were significantly lower in DM group compared with non-DM group. These changes were significantly improved in rats treated with propolis or insulin alone with greater significant effects in rats treated with both propolis and insulin.

Methods: Thirty Sprague-Dawley rats were randomly assigned to control (non-diabetic), PDN and non-PDN groups (n = 10). The rats were induced with diabetes by streptozotocin injection (60 mg/kg). Tactile allodynia and thermal hyperalgesia were assessed on day 0, 14 (week 2) and 21 (week 3) in the rats. The rats were sacrificed and the spinal cord tissue was collected for the measurement of oxidative stress (malondialdehyde (MDA), superoxide dismutase (SOD) and catalase) and pro-inflammatory markers (interleukin-1β (IL-1β) and tumour necrosis factor-α (TNF-α)).

Results: PDN rats demonstrated a marked tactile allodynia with no thermal hyperalgesia whilst non-PDN rats exhibited a prominent hypo-responsiveness towards non-noxious stimuli and hypoalgesia towards thermal input. The MDA level and pro-inflammatory TNF-α was significantly increased in PDN rats whilst catalase was reduced in these rats. Meanwhile, non-PDN rats demonstrated reduced SOD enzyme activity and TNF-α level and increased MDA and catalase activity.

AIMS OF STUDY: The aim of the present study is to evaluate the repeated dose toxicity of the standardized aqueous extract administered daily for 30 days through oral administration at its effective hypoglycemia doses.

MATERIALS AND METHODS: The seeds were dried, ground and extracted in deionized water. A HPLC-photodiode array method was developed and validated for the standardization of both the hypoglycemia agents, namely bruceine D and E in aqueous extract. Both normoglycemia and streptozotocin (STZ)-induced diabetic rats were fed orally with 15, 30 and 60mg/kg body weight of standardized aqueous extract. The blood glucose was measured at 0-8h. In repeated dose toxicity, similar doses were administered orally to rats for 30 days. At the end of 30 days, the blood was withdrawn and subjected to biochemical and haematology analysis while organs were harvested for histology analysis.

RESULTS: Oral administration of standardized aqueous extract exhibited a dose-response relationship in both the normoglycemia and STZ-induced diabetic rats. Daily oral administration of 15, 30 and 60mg/kg standardized aqueous extract for 30 days to rats did not show signs to toxicity in its biochemical, haematology and histology analysis.

METHODS: Sprague-Dawley rats were divided into normal control rats (N) which received vehicle, and diabetic rats which either received vehicle (DV) or 100 mg/kg of TRF (DT). Diabetes was induced with intraperitoneal injection of STZ (60 mg/kg body weight). Treatments were given orally, once daily, for 12 weeks after confirmation of hyperglycaemia. Fundus photographs were captured at baseline, 6- and 12-week post-STZ injection and average diameter of retinal veins and arteries were measured. At 12-week post-STZ injection, rats were euthanised, and retinae were collected for measurement of Ang-2 and PKC gene and protein expressions.