Pancreatic islet regeneration by ephedrine in mice with streptozotocin-induced diabetes

Abstract: In this experiment, we investigated the effects of crude Ephedrae herba, alkaloid extract of Ephedrae herba and 1-ephedrine, a major alkaloid component, on diabetic mice induced by streptozotocin (STZ). The alkaloid extract and 1-ephedrine showed suppression on the hyperglycemia. The suppression by Ephedrae herba of hyperglycemia may therefore be due to 1-ephedrine. Furthermore, we found that Ephedrae herba, alkaloid and 1-ephedrine promoted the regeneration of pancreas islets following atrophy induced by STZ. It is therefore suggested that Ephedrae herba may regenerate atrophied pancreatic islets, restore the secretion of insulin, and thus correct hyperglycemia.


Streptozotocin (STZ) is widely used experimentally to induce diabetes in animals (Zusman et al., 1985). The mechanism of diabetes induced by STZ is due to a change of the DNA chain in the pancreatic islets, a reduction in damage of the B cells (Okamoto, 1981).
The crude drug Ephedrae herba, obtained from the herb Ephedra sinica Stapf (Ephedraceae), has long been used for sudorific, antipyretic, antitussive and anti-inflammatory purposes in East-Asia. Diabetes is not included in the traditional applications of Ephedrae herba. However, we used an experimental model of mice with diabetes induced by STZ to investigate the effects of Mao-to, a Kampo formulation, and found that it could suppress the increase of blood glucose. Furthermore, Ephedrae herba, a major crude drug of Mao-to, protected the pancreas islet and improved the results of the glucose tolerance test (Kobayashi et al, 1998). Abundant alkaloid is found in Ephedrae herba, and the major component is ephedrine (Yamada et al., 1994).

In this study, we attempted to clarify the active components of Ephedrae herba, and used crude extract, alkaloid extract of Ephedrae herba and 1-ephedrine to investigate their effects on the diabetes induced in mice by STZ.
Materials and Methods
Animals
BALB/cA Jcl male mice were obtained from Clea Japan, Inc. at 8 weeks of age. They were kept in plastic cages with wood shavings, and maintained in an animal room, which was air-conditioned (22-24 [degrees]) and artificially illuminated, and provided with standard commercial pellets and tap water ad libitum.
Preparation of Samples
Ephedrae herba (Ephedra sinica Stapf) was obtained from Uchida Co. (Tokyo, Japan). 10 g of crude herb of Ephedrae herba was boiled with 600 ml of distilled water until the volume was reduced to 350 ml. The supernatant fluid was filtered and centrifuged. The yield was 15% from the original herb weight. Ephedrae herba was crushed into powder and extracted three times with ethanol; HCl was then added into the crude extracts and the resulting precipitate was collected. This was to provide 70 mg (0.7% yield) of the crude alkaloid extracts in the following experiment. Analytical grade of 1-ephedrine was purchased from Dainippon Pharmacy.
Induction of Diabetes
Mice were intraperitoneally injected with 200 mg/kg of streptozotocin (STZ, Sigma, USA) in 10 mM citrate buffer (pH 4.4) after 18 hours of fasting. Blood was then collected from the tail vein. Blood glucose levels were measured by the glucose dehydrogenase method on a portable glucometer (Yamanochi, Tokyo, Japan). On the 4th day after injection of STZ, mice showing 200-500 mg/dl blood glucose were divided into four groups. In the Ephedrae herba group, the herbal extract was diluted and given as drinking water consecutively for five weeks. The concentration of the extract was adjusted to 1.4 g/kg/day as original herb weight. In the alkaloid and 1-ephedrine groups, the samples were dissolved in tap water and given as drinking water. The concentration of the samples was adjusted to alkaloid fraction: 0.62 mg/kg body weight and 1-ephedrine: 0.62 mg/kg body weight, respectively. The samples administered for a mouse was 10-20 times the dose for human adults. The samples were administered orally consecutively from the 4th day after STZ injection for two weeks. Animals of the control group received only water. The numbers of mice in each group were as follows: control group 5, Ephedrae herba: 5, alkaloid fraction: 6 and 1-ephedrine: 6 mice.
Histological Analysis of the Pancreas
Two weeks after the administration, mice were killed by decapitation under light ether anesthesia and the pancreas was removed. Pancreatic tissue was fixed in 10% buffered formalin, and embedded in paraffin according to the conventional procedure. Paraffin sections were serially cut at 4[micro]m in thickness and stained with Hematoxylin. A part of the slide was refixed in Bouin solution and stained with Gomorri's aldehyde-fuchsin stain.
Statistics
Data were analyzed by Student's t-test, p<0.05 was considered statistically significant.
Results
Effects of Ephedrae herba and its Components on Blood Glucose
The mice showing hyperglycemia (200-500 mg/dl) were used to investigate the effects of Ephedrae herba extract, alkaloid extract and 1-ephedrine in the present experiment. The blood glucose was measured before administration and on the 3rd, 6th and 14th days after administration of samples. In the control group receiving only water, the blood glucose continued to be raised. The hyperglycemia was suppressed by all samples, but the period of this effect was different. The blood glucose in the Ephedrae herba extract group tended to decrease on the 3rd day, and significantly decrease by the 14th day, compared with the control group (p<0.05).>

source

Posted in: on วันศุกร์ที่ 8 กุมภาพันธ์ พ.ศ. 2551 at  

Aspergillosis of the petrous apex

We present the case of an immunocompetent man who presented with multiple and progressive cranial nerve palsies. The cause was found to be aspergillosis of the petrous bone, arising as a result of chronic fungal otitis media. Despite treatment with local excision and systemic anti fungal therapy, he died after suffering a subarachnoid haemorrhage.

Diagnosis rests upon prompt radiological imaging and the acquisition of tissue for histological examination and culture but cannot be made without awareness of the condition.

source

Posted in: on at  

Lesson of the week: a new cause of treatable dementia

Case report: a 69-year-old married British man presented with 4 months of falls and confusion. HIV antibody test, performed after exclusion of other diagnoses, was positive. Institution of triple antiretroviral therapy resulted in an almost complete recovery.

source

Posted in: on at  

Nutrition: A Key Link in Clinical Decision Trees

In 2003, Novartis Medical Nutrition, Fremont, MI, commissioned a panel of experts to develop a comprehensive pressure ulcer program for long-term-care facilities. As a result, the panel of physicians, nurses, dietitians, and physical therapists designed a unique series of decision trees intended to help guide clinicians working with elderly residents at risk for or currently being treated for pressure ulcers. Pressure ulcers are used as a quality indicator by the Centers for Medicare & Medicaid Services.
Decision trees are a systematic approach that reminds staff of the essential steps in approaching a unique clinical problem. Each individual tree expands on its components and develops that particular discipline's contribution to the overall care.


Panel Objectives
The panel's goal was to address the serious consequences of pressure ulcers, including lifestyle limitations, reduced selfesteem, altered body image, pain, delay in rehabilitation, and increased morbidity and mortality.1,2 To that end, the panel established these objectives:
* encourage a team approach to the care of chronic wounds such as pressure ulcers
* bring a cohesiveness to current facility wound care programs already in use
* offer guidelines to facilities without formal wound care protocols.
The panel developed a medical decision tree for the prevention and treatment of pressure ulcers. The physician uses this tree to refer the resident's care to the appropriate interdisplinary team member, such as nursing, nutrition, and physical therapy. Each discipline has its own decision tree to utilize in determining care for the resident.
Decision Tree in Action
After appropriate staff training, 5 Autumn Care long-term-care facilities in Virginia and North Carolina implemented the decision tree program (Figure 1, page 476). The new program was evaluated after 3 months. Nineteen residents who had either documented wounds or were at high risk for pressure ulcer development had been assessed.
In Group 1,12 residents were identified as being at high risk for pressure ulcers. Six residents did develop pressure ulcers during the 3-month period, with the wounds healing for 5 of the 6 residents during this time.
In Group 2, 7 residents had documented wounds at the start of the program: 5 had pressure ulcers, 1 had a stasis ulcer, and 1 had a surgical wound. At the conclusion of the 3-month trial period, wounds had healed in 5 of the 7 residents.
Implementing the decision tree process promoted collaboration between departments, especially nursing and dietary, and led to identification of nutrition and hydration issues that may not have been considered.
source

Posted in: on at  

Wound care technologies: Future unknown

At a recent meeting in Baltimore, MD, Grant Bagley, Director of Coverage and Analysis at the Health Care Financing Administration (HCFA), stated that Medicare coverage of chronic wound treatments-such as electrical stimulation and hyperbaric oxygen-are among the existing technologies that HCFA would like to review retrospectively, using more rigorous standards of evidence-based medicine.

One of the questions that HCFA has been pondering in terms of policies and practices for chronic wound healing is "whether hyperbaric oxygen therapy and electrical stimulation are even useful for chronic wound healing." Bagley stated that HCFA needs the flexibility to retrospectively apply more stringent evidence-based coverage standards to existing Medicare policies, citing chronic wound treatments as examples. It is not likely that formal review of old policies using evidencebased standards will occur frequently; however, when HCFA examines new technologies, coverage and payment policies for older products will likely be affected.
As HCFA reexamines coverage policies on older technologies, the newly created Medicare Coverage Advisory Committee will be providing input and a way for HCFA to demand and evaluate scientific evidence and data on clinical practice.

HCFA is working on a Federal Register notice on Medicare coverage criteria, which is planned for a fall release.

Karen Simon, JD, contributes to Policy & Practice. She is currently a Medicare consultant, Any information on reimbursement is provided as a service to readers but does not constitute, guarantee. or warranty that payment will be provided. Providers are responsible for case-bycase assessment of qualifications for reimbursement


Posted in: on at  

สมัครสมาชิก: บทความ (Atom)