H & E stains illustrating the effects of insulin-containing dermal patches on the morphology of the skin in STZ-induced diabetic rats.

<p>Picture A represents intact secretory ducts (white arrow), stratum basale (yellow arrow) and intact sebaceous glands (red arrow) of the untreated control animals. (Mag 8×500 µm). Picture B represents intact secretory ducts (white arrow), uninjured stratum basale (yellow arrow) and intact sebaceous glands (red arrow) of the PI treated animals. (Mag 8×500 µm). Pictures C represents intact secretory ducts (white arrow), uninjured stratum basale (yellow arrow) and intact sebaceous glands (red arrow) of the subcutaneously insulin treated animals (Mag 12×500 µm).</p

Comparison of the effects of topically applied PI hydrogel matrix patch and sc insulin on the the insulin-stimulated glycogen synthase (GS) and facilitative glucose transporter (GLUT4) in hepatic and skeletal muscle tissues of STZ-induced diabetic rats, respectively with untreated non-diabetic as determined by Western blotting.

<p>Values are expressed as mean ± S.E.M. Values were obtained from Western blots for six preparations. ★p<0.05 by comparison with non-diabetic animals. •p<0.05 by comparison with respective control animals.</p

Comparisons of the effects of PI matrix patches of different insulin concentrations on body weight, food and water intake in STZ-induced diabetic rats with untreated diabetic rats and control non-diabetic (ND) animals.

<p>Insulin was administered thrice daily for 5-weeks via subcutaneous injection or PI insulin matrices. Data are expressed as mean ± SEM, n = 6 in each group.</p><p>*<i>p<</i>0.05 by comparison with control non-diabetic (ND) animals.</p><p>♦p<0.05 by comparison with comparison with control STZ-induced diabetic rats.</p

Comparison of the effects on blood glucose of STZ-induced diabetic rats treated with transdermal PI hydrogel matrix patches on the skin and diabetic rats treated with sc insulin with untreated animals.

<p>Animals treated with drug-free pectin and subcutaneous insulin (175 µg/kg) acted as negative and positive controls, respectively. Values are presented as means, and vertical bars indicate SEM of means (n = 6 in each group). ★p<0.05 by comparison with control animals.</p

Immunohistochemical micrographs illustrating the effects of transdermally delivered insulin on the expression of Insulin receptor (IR) in skin sections of STZ-induced diabetic rats.

<p>The presence of IRS is depicted as brown staining and a method control (A) reveals no immune-reactivity and intense haematoxylin staining (blue) across epidermis and dermis. Untreated non-diabetic rat skin section (B) revealed widespread localization of IRS across the epidermis and dermis. Untreated diabetic control rat skin section (C) exhibited very low immuno-reactivity predominantly in the dermis. Intense immuno-reactivity was observed in the epidemis, dermis and subcutaneous layer of transdermal insulin treated rat skin section (D). Subcutaneous insulin treated rat skin section (E) also exhibited widespread localization of IRS in the epidermis and dermal structures (Mag. 4×500×µm). All the dermal structures including, collagen and hair follicles were positive for IRS with more intensity in the transdermal treatment (F; Mag 27×100 µm).</p

Comparisons of OGT responses (A) and AUC_glucose (B) of STZ-induced diabetic rats to PI matrix patches of different insulin concentrations with control animals.

<p>Values are presented as means, and vertical bars indicate SEM of means (n = 6 in each group). ★p<0.05 by comparison with control animals.</p

Comparison of plasma insulin concentrations of STZ-induced diabetic rats to PI matrix patches of different insulin concentrations with control animals.

<p>Values are presented as means, and vertical bars indicate SEM of means (n = 6 in each group). ♦p<0.05 by comparison Non-diabetic control. ★p<0.05 by comparison to STZ-induced diabetic control. •p<0.05 by comparison to the lowest dose. ∞ p<0.05 by comparison to transdermally PI treated animals.</p

¹H (A) and ¹³C (B) NMR of oleanolic acid in dissolved in chloroform.

<p>¹H (A) and ¹³C (B) NMR of oleanolic acid in dissolved in chloroform.</p

Inhibitory effects of OD and MA on blood glucose increases in non-diabetic (A and B) and STZ-induced diabetic (C and D) rats after sucrose and starch loading for 2h.

<p>The area under the curve for glucose (AUC_glucose) was calculated by incremental method. Values are presented as means, and vertical bars indicate SEM (n = 6 rats in each group). ★p < 0.05 by comparison with control animals.</p

Comparison of OGT responses to OA and MA in non-diabetic (A and B) and STZ- induced diabetic (C and D) rats after sucrose and starch loading.

<p>Values are presented as means, and vertical bars indicate SEM (n=6 rats in each group). ★ p<0.05 by comparison with control animals.</p