Radix Astragali and Radix Rehmanniae, the principal components of two antidiabetic foot ulcer herbal formulae, elicit viability-promoting effects on primary fibroblasts cultured from diabetic foot ulcer tissues.

Over 194 million people suffer from diabetes worldwide. The improper control of diabetes may result in diabetic foot ulcer or even amputation. Herbal medicine provides a means for treating diabetic foot ulcers for a large population in developing countries. The wound healing-enhancing activities of the principal herbs, Radix Astragali (RA) and Radix Rehmanniae (RR) in two clinically efficacious Chinese herbal formulae were studied in primary fibroblasts from diabetic foot ulcer patients. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that RA and RR significantly enhanced the viability of fibroblasts isolated from foot ulcers of diabetic patients, even from those with no response to insulin treatment. The results in this study indicate that fibroblast viability enhancement effects of RA and RR likely underlie the healing effects of F1 and F2 in diabetic foot ulcers.

Lau TW ，Chan YW ，Lau CP ，Lau KM ，Lau CB ，Fung KP ，Leung PC ，Ho YY ... -  《-》

Investigation of the effects of Chinese medicine on fibroblast viability: implications in wound healing.

Lau TW ，Chan YW ，Lau CP ，Chan CM ，Lau CB ，Fung KP ，Leung PC ，Ho YY ... -  《-》

An in vivo investigation on the wound-healing effect of two medicinal herbs using an animal model with foot ulcer.

Over 190 million people in the world suffer from diabetes mellitus. Diabetics are 25 times more likely to have a leg amputated because of unhealing foot ulcers. Herbal medicine has been used in China to salvage the ulcerated limb. With the aim to study the efficacy of two commonly used herbs for ulcer healing, namely Radix Astragali and Radix Rehmanniae, a good animal model needs to be developed for a proper in vivo investigation. Firstly, a diabetic animal model was established by streptozotocin injection. Then standard wounds were created on the feet of the diabetic rats. Digital photographs were taken and analyzed by a novel image analysis software. The average ulcer area in the Radix Rehmanniae treatment group was 11.45 mm2, which was significantly smaller than the 15.12 mm2 in the water treatment group (p = 0.04). Radix Astragali, on the other hand, was found to have no significant effect on ulcer shrinkage. Further investigation is needed for the identification of the active principles of Radix Rehmanniae.

Lau TW ，Sahota DS ，Lau CH ，Chan CM ，Lam FC ，Ho YY ，Fung KP ，Lau CB ，Leung PC ... -  《-》

Synergistic interaction between Astragali Radix and Rehmanniae Radix in a Chinese herbal formula to promote diabetic wound healing.

Astragali Radix (AR) and Rehmanniae Radix (RR) are two traditional Chinese medicines widely used in China for treating diabetes mellitus and its complications, such as diabetic foot ulcer. In our previous study, a herbal formula NF3 comprising AR and RR in the ratio of 2:1 was found effective in enhancing diabetic wound healing in rats through the actions of tissue regeneration, angiogenesis promotion and inflammation inhibition. The aims of the present study were to investigate the herb-herb interaction (or the possible synergistic effect) between AR and RR in NF3 to promote diabetic wound healing and to identify the principal herb in the formula by evaluating the potencies of individual AR and RR in different mechanistic studies. A chemically induced diabetic foot ulcer rat model was used to examine the wound healing effect of NF3 and its individual herbs AR and RR. For mechanistic studies, murine macrophage cell (RAW 264.7) inflammation, human fibroblast (Hs27) proliferation and human endothelial cell (HMEC-1) migration assays were adopted to investigate the anti-inflammatory, granulation formation and angiogenesis-promoting activities of the herbal extracts, respectively. In the foot ulcer animal model, neither AR nor RR at clinical relevant dose (0.98g/kg) promoted diabetic wound healing. However, when they were used in combination as NF3, synergistic interaction was demonstrated, of which NF3 could significantly reduce the wound area of rats when compared to water group (p<0.01). For anti-inflammation and granulation formation, AR was more effective than RR in inhibiting lipopolysaccharide (LPS)-induced nitric oxide production from RAW 264.7 cells and promoting Hs27 fibroblast proliferation. In the aspect of angiogenesis promotion, only NF3 promoted cell migration of HMEC-1 cells. AR plays a preeminent role in the anti-inflammatory and fibroblast-proliferating activities of NF3. The inclusion of RR, however, is crucial for NF3 to exert its overall wound-healing as well as the underlying angiogenesis-promoting effects. The results of present study justified the combined usage of AR and RR in the ratio of 2:1 as NF3 to treat diabetic foot ulcer and illustrated that AR is the principal herb in this herbal formula.

Lau KM ，Lai KK ，Liu CL ，Tam JC ，To MH ，Kwok HF ，Lau CP ，Ko CH ，Leung PC ，Fung KP ，Poon SK ，Lau CB ... -  《-》

Influence of an anti-diabetic foot ulcer formula and its component herbs on tissue and systemic glucose homeostasis.

Chan CM ，Chan YW ，Lau CH ，Lau TW ，Lau KM ，Lam FC ，Che CT ，Leung PC ，Fung KP ，Lau CB ，Ho YY ... -  《-》