Amelioration of Diabetes and Painful Diabetic Neuropathy by Punica granatum L. Extract and Its Spray Dried Biopolymeric Dispersions

Abstract

Aims. To evaluate the effect of Punica granatum (Pg) rind extract and its spray dried biopolymeric dispersions with casein (F1) or chitosan (F2) against Diabetes mellitus (DM) and diabetic neuropathy (DN). Methods. We measured the acute (6 h) and subacute (8 days) effect of various doses of Pg, F1, and F2 and the active compounds on alloxan-induced DM mouse model. We evaluated DN utilizing latency tests for longer period of time (8 weeks). In addition, the in vivo antioxidant activity was assessed utilizing serum catalase level. Results. The results proved that the highest dose levels of Pg extract, F1, F2 exerted remarkable hypoglycemic activity with 48, 52, and 40% drop in the mice glucose levels after 6 hours, respectively. The tested compounds also improved peripheral nerve function as observed from the latency tests. Bioguided fractionation suggested that gallic acid (GA) was Pg main active ingredient responsible for its actions. Conclusion. Pg extract, F1, F2, and GA could be considered as a new therapeutic potential for the amelioration of diabetic neuropathic pain and the observed in vivo antioxidant potential may be involved in its antinociceptive effect. It is highly significant to pay attention to Pg and GA for amelioration and control of DM and its complications.

Figure 1

In vitro release pattern of P. granatum L. extract from different biopolymeric dispersions of casein (F1) and chitosan (F2).

Figure 2

Effect of P. granatum ethanolic extract (Pg) and tramadol (TRA) 10 mg/kg, as positive control, on the hot plate and tail withdrawal latencies in alloxan-induced diabetic mice. (a) Hot plate latency: NORM: normal control mice (crossed-triangles, straight line); DIA + VEH: diabetic animals treated with vehicle as control (closed-squares, straight-line); positive control TRA 10 mg/kg: alloxan treated mice with TRA 10 mg/kg (solid-stars, dotted-line); DIA + Pg 25 mg/kg: diabetic animals treated with Pg 25 mg/kg (solid-circles, straight-line); DIA + Pg 50 mg/kg: diabetic animals treated with Pg 50 mg/kg (up-triangles, dashed-line); DIA + Pg 100 mg/kg: diabetic animals treated with Pg 100 mg/kg (right-triangles, dashed-dotted-line). (b) Tail withdrawal latency: NORM: normal control mice (crossed-triangles, straight line); DIA + VEH: diabetic animals treated with vehicle as control (closed-squares, straight-line); positive control TRA 10 mg/kg: alloxan treated mice with TRA 10 mg/kg (solid-stars, dotted-line); DIA + Pg 25 mg/kg: diabetic animals treated with Pg 25 mg/kg (solid-circles, straight-line); DIA + Pg 50 mg/kg: diabetic animals treated with Pg 50 mg/kg (up-triangles, dashed-line); DIA + Pg 100 mg/kg: diabetic animals treated with Pg 100 mg/kg (right-triangles, dashed-dotted-line). Data are expressed in mean ± SEM. “∗” means P < 0.05 compared with vehicle. “∗∗” means P < 0.01 compared with vehicle.

Figure 3

Effect of F1 and TRA 10 mg/kg, as positive control, on the hot plate and tail withdrawal latencies in alloxan-induced diabetic mice. (a) Hot plate latency: NORM: normal control mice (crossed-triangles, straight line); DIA + VEH: diabetic animals treated with vehicle as control (closed-squares, straight-line); placebo F1: diabetic animals treated with placebo F1 200 mg/kg (crossed-squares, dashed-line); positive control TRA 10 mg/kg: alloxan treated mice with TRA 10 mg/kg (solid-stars, dotted-line); DIA + F1 50 mg/kg: diabetic animals treated with F1 50 mg/kg (solid-circles, straight-line); DIA + F1 100 mg/kg: diabetic animals treated with F1 100 mg/kg (up-triangles, dashed-line); DIA + F1 200 mg/kg: diabetic animals treated with Pg F1 200 mg/kg (right-triangles, dashed-dotted-line). (b) Tail withdrawal latency: NORM: normal control mice (crossed-triangles, straight line); DIA + VEH: diabetic animals treated with vehicle as control (closed-squares, straight-line); placebo F1: diabetic animals treated with placebo F1 200 mg/kg (crossed-squares, dashed-line); positive control TRA 10 mg/kg: alloxan treated mice with TRA 10 mg/kg (solid-stars, dotted-line); DIA + F1 50 mg/kg: diabetic animals treated with F1 50 mg/kg (solid-circles, straight-line); DIA + F1 100 mg/kg: diabetic animals treated with F1 100 mg/kg (up-triangles, dashed-line); DIA + F1 200 mg/kg: diabetic animals treated with F1 200 mg/kg (right-triangles, dashed-dotted-line). Data are expressed in mean ± SEM. “∗” means P < 0.05 compared with vehicle. “∗∗” means P < 0.01 compared with vehicle.

Figure 4

Effect of F2 and TRA 10 mg/kg, as positive control, on the hot plate and tail withdrawal latencies in alloxan-induced diabetic mice. (a) Hot plate latency: NORM: normal control mice (crossed-triangles, straight line); DIA + VEH: diabetic animals treated with vehicle as control (closed-squares, straight-line); placebo F2: diabetic animals treated with placebo F2 200 mg/kg (crossed-squares, dashed-line); positive control TRA 10 mg/kg: alloxan treated mice with TRA 10 mg/kg (solid-stars, dotted-line); DIA + F2 50 mg/kg: diabetic animals treated with F2 50 mg/kg (solid-circles, straight-line); DIA + F2 100 mg/kg: diabetic animals treated with F2 100 mg/kg (up-triangles, dashed-line). DIA + Pg 200 mg/kg: diabetic animals treated with F2 200 mg/kg (right-triangles, dashed-dotted-line). (b) Tail withdrawal latency: NORM: normal control mice (crossed-triangles, straight line); DIA + VEH: diabetic animals treated with vehicle as control (closed-squares, straight-line); placebo F2: diabetic animals treated with placebo F2 200 mg/kg (crossed-squares, dashed-line); positive control TRA 10 mg/kg: alloxan treated mice with TRA 10 mg/kg (solid-stars, dotted-line). DIA + F2 50 mg/kg: diabetic animals treated with F2 50 mg/kg (solid-circles, straight-line); DIA + F2 100 mg/kg: diabetic animals treated with F2 100 mg/kg (up-triangles, dashed-line). DIA + F2 200 mg/kg: diabetic animals treated with F2 200 mg/kg (right-triangles, dashed-dotted-line). Data are expressed in mean ± SEM. “∗” means P < 0.05 compared with vehicle. “∗∗” means P < 0.01 compared with vehicle.

Figure 5

Effect of gallic acid (GA) and tramadol (TRA) 10 mg/kg, as positive control, on the hot plate and tail withdrawal latencies in alloxan-induced diabetic mice. (a) Hot plate latency: NORM: normal control mice (crossed-triangles, straight line); DIA + VEH: diabetic animals treated with vehicle as control (closed-squares, straight-line); positive control TRA 10 mg/kg: alloxan treated mice with TRA 10 mg/kg (solid-stars, dotted-line); DIA + GA 3 mg/kg: diabetic animals treated with GA 3 mg/kg (solid-circles, straight-line); DIA + GA 6 mg/kg: diabetic animals treated with GA 6 mg/kg (up-triangles, dashed-line). DIA + Pg 12 mg/kg: diabetic animals treated with GA 12 mg/kg (right-triangles, dashed-dotted-line). (b) Tail withdrawal latency: NORM: normal control mice (crossed-triangles, straight line); DIA + VEH: diabetic animals treated with vehicle as control (closed-squares, straight-line); positive control TRA 10 mg/kg: alloxan treated mice with TRA 10 mg/kg (solid-stars, dotted-line); DIA + GA 3 mg/kg: diabetic animals treated with GA 3 mg/kg (solid-circles, straight-line); DIA + GA 6 mg/kg: diabetic animals treated with GA 6 mg/kg (up-triangles, dashed-line); DIA + GA 12 mg/kg: diabetic animals treated with GA 12 mg/kg (right-triangles, dashed-dotted-line). Data are expressed in mean ± SEM. “∗” means P < 0.05 compared with vehicle. “∗∗” means P < 0.01 compared with vehicle.