Immunotherapy after recent-onset type 1 diabetes: combinatorial treatment for achieving long-term remission in humans?

Evaluation of antidiabetic potential of selected traditional Chinese medicines in STZ-induced diabetic mice

AIMS

Traditional Chinese medicine (TCM) has been used for treating complex chronic diseases owing to their fewer side-effects, better patient tolerance and relatively less cost. The present work was carried out to study the anti-diabetic efficacy and mechanisms of 34 TCMs.

MATERIALS AND METHODS

Streptozotocin (STZ)-diabetic mice were orally administrated with corresponding herbal solution once a day for 4 weeks. At the end of experiment, the level of plasma glucose, malondialdehyde (MDA), the activity of superoxide dismutase (SOD) and the serum aldose reductase (AR) were determined, the effects of TCM extract on α-glucosidase and angiotensin-converting enzyme (ACE) in vitro were also evaluated.

RESULTS

13 out of the 34 herbs showed a statistically significant plasma glucose lowering action compared with the diabetic control group. Biochemical analysis revealed that Atractylodes macrocephala, Codonopsis pilosula, Dioscorea opposite, Flos lonicerae and Pueraria lobata may retard the progression of diabetes via reduce the blood glucose level and prevent the increase of AR activity. Other tested herbs, such as Ramulus cinnamomi, Cinnamomum cassia, and Eucommia ulmoides, showed the antidiabetic ability by either prevent the decrease in SOD activity or suppress the increase of MDA. Zymologic assay reveals that Pueraria lobata and Anemarrhena asphodeloides showed the highest inhibition against α-glucosidase and ACE respectively. Interestingly, the post-treatment glucose levels and AR activity were positively correlated with kidney/body weight of 34 herbs treated diabetic mice (p = 0.02, 0.04 respectively).

CONCLUSIONS

Several potential antidiabetic herbs derived from Chinese traditional pharmacopeia such as Dioscorea opposite, Pueraria lobata, Codonopsis pilosula and Ramulus cinnamomi, have been found to exert a beneficial action on diabetes and diabetic complications via multi-mechanisms.

An update on preventive and regenerative therapies in diabetes mellitus

Type 1A (immune-mediated) and type 2 diabetes mellitus are two of the most common severe chronic illnesses, affecting over 230 million people worldwide with an estimated global prevalence of 5.1%. Although type 1 and type 2 diabetes differ greatly in modes of pathogenesis, these illnesses share a common pathology and consequences characterized by loss of functional beta-cell mass and subsequent dysregulation of carbohydrate and lipid metabolism. Since therapy for diabetes and the associated complications poses enormous public health and economic burdens, novel preventive and regenerative therapies have emerged in the past decade with the aim to preserve beta-cell mass and delay the onset of diabetes. The goal of this review is to provide a comprehensive overview of current efforts in the fight against diabetes, and attempts to document all strategies that have emerged in clinical studies within the past 25 years. First, strategies to identify individuals at risk, ranging from whole-genome scans to autoantibody screening, will be discussed. Second, novel approaches to prevent or delay the onset of disease will be covered. Particular focus is given on emerging strategies for individuals at risk for type 1 diabetes that target T-cell regulation and induction of tolerance, while new pharmaceutical concepts in combination with lifestyle interventions are discussed within the scope of type 2 diabetes prevention. Lastly, important efforts to halt disease progression with emphasis on beta-cell regeneration are presented.

Stopping diabetes in its tracks: autologous non-myeloablative stem cell transplantation

A recent report in this year’s April issue of Journal of the American Medical Association describes an unprecedented success in delaying insulin dependence in patients with recent-onset Type 1 diabetes after non-myeloablative immune suppression with cyclophosphamide and antithymocyte globulin followed by autologous stem cell transplantation. In this study, 14 out of 15 patients became insulin-independent, which lasted up to 35 months. Concomitantly, C-peptide levels increased substantially compared with preintervention values. Treatment of autoimmune disorders, and in particular Type 1 diabetes, constitutes a complex balancing act between suppressing autoaggressive responses strongly and permanently enough, while circumventing much-feared long-term side effects from chronic immunosuppression. This clinical Phase I/II trial is relevant to fine-tuning interventive protocols and contributing to the further development of suitable combination therapies to prevent and treat Type 1 diabetes.